2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2961
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC U2142 00
- Lost Communication With Yaw Rate Sensor (YRS)
Circuit/System Description
Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating
information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be
exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an
availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the
ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus
serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain
Management/Computers and Control Systems/Information Bus/Description and Operation).
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter module availability has not been received.
Action Taken When the DTC Sets
* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.
* System OFF lamps will illuminate for these systems.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Diagnostic Aids
* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no
associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are
transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically
after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:
- A control module on the data communication circuit was disconnected while the communication circuit is awake.
- Power to one or more modules was interrupted during diagnosis.
- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.
- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.
- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.
These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.
* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between
control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a
control module based only on a history U-code.
* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication
issue.
* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system
inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.
* Use to determine if the module uses high or low speed GMLAN serial data communications.
* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and
the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control
module.
* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,
providing the vehicle is equipped with the control module.
Showing posts with label * Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure. Show all posts
Showing posts with label * Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure. Show all posts
Sunday, December 20, 2020
Friday, December 18, 2020
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2904
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2904
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC U2142 00
- Lost Communication With Yaw Rate Sensor (YRS)
Circuit/System Description
Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating
information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be
exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an
availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the
ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus
serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain
Management/Computers and Control Systems/Information Bus/Description and Operation).
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter module availability has not been received.
Action Taken When the DTC Sets
* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.
* System OFF lamps will illuminate for these systems.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Diagnostic Aids
* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no
associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are
transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically
after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:
- A control module on the data communication circuit was disconnected while the communication circuit is awake.
- Power to one or more modules was interrupted during diagnosis.
- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.
- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.
- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.
These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.
* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between
control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a
control module based only on a history U-code.
* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication
issue.
* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system
inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.
* Use to determine if the module uses high or low speed GMLAN serial data communications.
* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and
the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control
module.
* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,
providing the vehicle is equipped with the control module.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC U2142 00
- Lost Communication With Yaw Rate Sensor (YRS)
Circuit/System Description
Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating
information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be
exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an
availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the
ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus
serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain
Management/Computers and Control Systems/Information Bus/Description and Operation).
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter module availability has not been received.
Action Taken When the DTC Sets
* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.
* System OFF lamps will illuminate for these systems.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Diagnostic Aids
* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no
associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are
transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically
after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:
- A control module on the data communication circuit was disconnected while the communication circuit is awake.
- Power to one or more modules was interrupted during diagnosis.
- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.
- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.
- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.
These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.
* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between
control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a
control module based only on a history U-code.
* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication
issue.
* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system
inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.
* Use to determine if the module uses high or low speed GMLAN serial data communications.
* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and
the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control
module.
* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,
providing the vehicle is equipped with the control module.
Wednesday, December 2, 2020
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2535
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2535
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P2635
- Fuel Pump Flow Performance
Diagnostic Fault Information
Circuit/System Description
The engine control module (ECM) supplies voltage to the fuel pump control module when the ECM detects that the ignition is on. The voltage from
the ECM to the fuel pump control module remains active for 2 seconds, unless the engine is in crank or run. While this voltage is being received,
the fuel pump control module closes the ground switch of the fuel pump and also supplies a varying voltage to the fuel tank pump module in order
to maintain the desired fuel rail pressure.
Conditions for Running the DTC
* DTC P018B, P018C, P018D, P0231, P0232, P023F, P064A, P1255 or P06A6 are not active.
* DTC P0641 has not failed this ignition cycle.
* Fuel pump control is enabled and the fuel pump control state is normal.
* The system voltage is greater than 11 V.
* The engine has been running for more than 30 seconds.
Conditions for Setting the DTC
This DTC sets when the fuel pump control module detects a predetermined fuel pressure performance degradation between the desired fuel rail
pressure and the current fuel rail pressure.
Action Taken When the DTC Sets
DTC P2635 is a Type B DTC.
Conditions for Clearing the DTC
DTC P2635 is a Type B DTC.
Diagnostic Aids
Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records
can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the
diagnostic test reported a pass and/or a fail.
Reference Information
Schematic Reference
Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Fuel System Description (See: Powertrain Management/Computers and Control Systems/Description and Operation/Fuel System Description)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P2635
- Fuel Pump Flow Performance
Diagnostic Fault Information
Circuit/System Description
The engine control module (ECM) supplies voltage to the fuel pump control module when the ECM detects that the ignition is on. The voltage from
the ECM to the fuel pump control module remains active for 2 seconds, unless the engine is in crank or run. While this voltage is being received,
the fuel pump control module closes the ground switch of the fuel pump and also supplies a varying voltage to the fuel tank pump module in order
to maintain the desired fuel rail pressure.
Conditions for Running the DTC
* DTC P018B, P018C, P018D, P0231, P0232, P023F, P064A, P1255 or P06A6 are not active.
* DTC P0641 has not failed this ignition cycle.
* Fuel pump control is enabled and the fuel pump control state is normal.
* The system voltage is greater than 11 V.
* The engine has been running for more than 30 seconds.
Conditions for Setting the DTC
This DTC sets when the fuel pump control module detects a predetermined fuel pressure performance degradation between the desired fuel rail
pressure and the current fuel rail pressure.
Action Taken When the DTC Sets
DTC P2635 is a Type B DTC.
Conditions for Clearing the DTC
DTC P2635 is a Type B DTC.
Diagnostic Aids
Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records
can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the
diagnostic test reported a pass and/or a fail.
Reference Information
Schematic Reference
Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Fuel System Description (See: Powertrain Management/Computers and Control Systems/Description and Operation/Fuel System Description)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Thursday, November 19, 2020
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2208
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2208
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P0645
- A/C Clutch Relay Control Circuit
Diagnostic Fault Information
Circuit System Description
Ignition voltage is supplied directly to the A/C compressor clutch relay. The engine control module (ECM) controls the relay by grounding the A/C
clutch relay control circuit. When the ECM is commanding a component ON, the voltage of the control circuit should be near 0 volt. When the
ECM is commanding the control circuit to a component OFF, the voltage potential of the circuit should be near battery voltage.
Conditions for Running the DTC
* The ignition voltage is between 11-18 volts.
* The engine speed is greater than 600 RPM.
* An A/C request is made.
Conditions for Setting the DTCs
The ECM detects an open on the control circuit of the A/C compressor clutch relay when commanded OFF with the engine in crank or run status.
Action Taken When the DTC Sets
The ECM will store conditions which were present when the DTC set as Failure Records data only. This information will not be stored as Freeze
Frame data.
Conditions for Clearing the DTC
A history DTC clears after 40 consecutive warm-up cycles have occurred without a malfunction.
Reference Information
Schematic Reference
HVAC Schematics (See: Heating and Air Conditioning/Diagrams/Electrical Diagrams/HVAC - Automatic)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
* Air Delivery Description and Operation (See: Heating and Air Conditioning/Description and Operation/HVAC - Automatic/Air Delivery
Description and Operation)
* Air Temperature Description and Operation (See: Heating and Air Conditioning/Description and Operation/HVAC - Automatic/Air
Temperature Description and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P0645
- A/C Clutch Relay Control Circuit
Diagnostic Fault Information
Circuit System Description
Ignition voltage is supplied directly to the A/C compressor clutch relay. The engine control module (ECM) controls the relay by grounding the A/C
clutch relay control circuit. When the ECM is commanding a component ON, the voltage of the control circuit should be near 0 volt. When the
ECM is commanding the control circuit to a component OFF, the voltage potential of the circuit should be near battery voltage.
Conditions for Running the DTC
* The ignition voltage is between 11-18 volts.
* The engine speed is greater than 600 RPM.
* An A/C request is made.
Conditions for Setting the DTCs
The ECM detects an open on the control circuit of the A/C compressor clutch relay when commanded OFF with the engine in crank or run status.
Action Taken When the DTC Sets
The ECM will store conditions which were present when the DTC set as Failure Records data only. This information will not be stored as Freeze
Frame data.
Conditions for Clearing the DTC
A history DTC clears after 40 consecutive warm-up cycles have occurred without a malfunction.
Reference Information
Schematic Reference
HVAC Schematics (See: Heating and Air Conditioning/Diagrams/Electrical Diagrams/HVAC - Automatic)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
* Air Delivery Description and Operation (See: Heating and Air Conditioning/Description and Operation/HVAC - Automatic/Air Delivery
Description and Operation)
* Air Temperature Description and Operation (See: Heating and Air Conditioning/Description and Operation/HVAC - Automatic/Air
Temperature Description and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Monday, November 2, 2020
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 1803
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 1803
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0131
- HO2S Circuit Low Voltage Bank 1 Sensor 1
DTC P0132
- HO2S Circuit High Voltage Bank 1 Sensor 1
DTC P0137
- HO2S Circuit Low Voltage Bank 1 Sensor 2
DTC P0138
- HO2S Circuit High Voltage Bank 1 Sensor 2
DTC P0151
- HO2S Circuit Low Voltage Bank 2 Sensor 1
DTC P0152
- HO2S Circuit High Voltage Bank 2 Sensor 1
DTC P0157
- HO2S Circuit Low Voltage Bank 2 Sensor 2
DTC P0158
- HO2S Circuit High Voltage Bank 2 Sensor 2
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The heated oxygen sensors (HO2S) are used for fuel control and catalyst monitoring. Each HO2S compares the oxygen content of the surrounding
air with the oxygen content of the exhaust stream. When the engine is started, the control module operates in an Open Loop mode, ignoring the
HO2S signal voltage while calculating the air-to-fuel ratio. While the engine runs, the HO2S heats up and begins to generate a voltage within a
range of 0-1,275 mV. Once sufficient HO2S voltage fluctuation is observed by the control module, Closed Loop is entered. The control module
uses the HO2S voltage to determine the air-to-fuel ratio. An HO2S voltage that increases toward 1,000 mV indicates a rich fuel mixture. An HO2S
voltage that decreases toward 0 mV indicates a lean fuel mixture.
The heating elements inside each HO2S heat the sensor to bring the sensor up to operating conditions faster. This allows the system to enter Closed
Loop earlier and the control module to calculate the air-to-fuel ratio sooner.
Conditions for Running the DTC
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0131
- HO2S Circuit Low Voltage Bank 1 Sensor 1
DTC P0132
- HO2S Circuit High Voltage Bank 1 Sensor 1
DTC P0137
- HO2S Circuit Low Voltage Bank 1 Sensor 2
DTC P0138
- HO2S Circuit High Voltage Bank 1 Sensor 2
DTC P0151
- HO2S Circuit Low Voltage Bank 2 Sensor 1
DTC P0152
- HO2S Circuit High Voltage Bank 2 Sensor 1
DTC P0157
- HO2S Circuit Low Voltage Bank 2 Sensor 2
DTC P0158
- HO2S Circuit High Voltage Bank 2 Sensor 2
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The heated oxygen sensors (HO2S) are used for fuel control and catalyst monitoring. Each HO2S compares the oxygen content of the surrounding
air with the oxygen content of the exhaust stream. When the engine is started, the control module operates in an Open Loop mode, ignoring the
HO2S signal voltage while calculating the air-to-fuel ratio. While the engine runs, the HO2S heats up and begins to generate a voltage within a
range of 0-1,275 mV. Once sufficient HO2S voltage fluctuation is observed by the control module, Closed Loop is entered. The control module
uses the HO2S voltage to determine the air-to-fuel ratio. An HO2S voltage that increases toward 1,000 mV indicates a rich fuel mixture. An HO2S
voltage that decreases toward 0 mV indicates a lean fuel mixture.
The heating elements inside each HO2S heat the sensor to bring the sensor up to operating conditions faster. This allows the system to enter Closed
Loop earlier and the control module to calculate the air-to-fuel ratio sooner.
Conditions for Running the DTC
Friday, October 30, 2020
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 1737
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 1737
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P079B
- Transmission Clutch 2 Slip Detected
Circuit/System Description
The transmission control module monitors hybrid direct, 2-3-4 clutch slip speed when the hybrid direct, 2-3-4 clutch is applied. The hybrid direct,
2-3-4 clutch is displayed as Clutch 2 on the scan tool. The transmission control module is part of the control solenoid valve assembly and is not
serviced separately.
Conditions for Running the DTC
* Hybrid direct, 2-3-4 clutch is applied.
* The clutch pressure control solenoid 3 commanded pressure is 1800 kPa (261 psi) for 3 seconds.
Conditions for Setting the DTC
The transmission control module detects the hybrid direct, 2-3-4 clutch slip speed is greater than 200 RPM for 3 seconds.
Action Taken When the DTC Sets
* P079B is a Type B DTC.
* The transmission control module inhibits gear 2, gear 3, gear 4 and EVT 2.
Conditions for Clearing the DTC
P079B is a Type B DTC.
Diagnostic Aids
When attempting to set transmission performance DTCs, observe the Freeze Frame and Failure Records to assist in duplicating the failure
conditions. Ensure the transmission fluid level is correct and there are no leaks. If there are any other transmission DTCs set, diagnose those first.
Reference Information
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Circuit/System Verification
1. Verify that DTCs P0721, P0722, P0723, P0966, P0967, P0969, P0970, P0971, P0973, P0974, P0976, P0977, P2720, P2721, P2728, P2729,
or P2730 is not set.
瀚慖f any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code
Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle).
2. Perform the Transmission Fluid Level and Condition Check (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Testing
and Inspection/Symptom Related Diagnostic Procedures/2ML70 - Automatic Transmission/Transmission Fluid Level and Condition Check)
to verify correct fluid level.
3. Perform the Line Pressure Check (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Testing and Inspection/Component
Tests and General Diagnostics/2ML70 - Automatic Transmission/Line Pressure Check) to verify correct oil pressure.
4. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (See: Transmission and Drivetrain/Automatic
Transmission/Transaxle/Testing and Inspection/Component Tests and General Diagnostics/2ML70 - Automatic Transmission/Control
Solenoid Valve and Transmission Control Module Assembly Inspection) to verify control solenoid valve assembly condition.
5. Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test (See: Transmission and
Drivetrain/Automatic Transmission/Transaxle/Testing and Inspection/Component Tests and General Diagnostics/2ML70 - Automatic
Transmission/Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test) to verify control solenoid
valve assembly function.
6. Inspect the trans fluid pump ball check valve for possible sticking or damage.
瀚慖f the check ball is stuck or damaged, replace the check ball.
7. Inspect the hybrid direct, 2-3-4 clutch regulator valve for sticking or damage.
瀚慖f you found a concern with the hybrid direct, 2-3-4 clutch regulator valve, repair or replace the valve or valve body.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P079B
- Transmission Clutch 2 Slip Detected
Circuit/System Description
The transmission control module monitors hybrid direct, 2-3-4 clutch slip speed when the hybrid direct, 2-3-4 clutch is applied. The hybrid direct,
2-3-4 clutch is displayed as Clutch 2 on the scan tool. The transmission control module is part of the control solenoid valve assembly and is not
serviced separately.
Conditions for Running the DTC
* Hybrid direct, 2-3-4 clutch is applied.
* The clutch pressure control solenoid 3 commanded pressure is 1800 kPa (261 psi) for 3 seconds.
Conditions for Setting the DTC
The transmission control module detects the hybrid direct, 2-3-4 clutch slip speed is greater than 200 RPM for 3 seconds.
Action Taken When the DTC Sets
* P079B is a Type B DTC.
* The transmission control module inhibits gear 2, gear 3, gear 4 and EVT 2.
Conditions for Clearing the DTC
P079B is a Type B DTC.
Diagnostic Aids
When attempting to set transmission performance DTCs, observe the Freeze Frame and Failure Records to assist in duplicating the failure
conditions. Ensure the transmission fluid level is correct and there are no leaks. If there are any other transmission DTCs set, diagnose those first.
Reference Information
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Circuit/System Verification
1. Verify that DTCs P0721, P0722, P0723, P0966, P0967, P0969, P0970, P0971, P0973, P0974, P0976, P0977, P2720, P2721, P2728, P2729,
or P2730 is not set.
瀚慖f any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code
Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle).
2. Perform the Transmission Fluid Level and Condition Check (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Testing
and Inspection/Symptom Related Diagnostic Procedures/2ML70 - Automatic Transmission/Transmission Fluid Level and Condition Check)
to verify correct fluid level.
3. Perform the Line Pressure Check (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Testing and Inspection/Component
Tests and General Diagnostics/2ML70 - Automatic Transmission/Line Pressure Check) to verify correct oil pressure.
4. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (See: Transmission and Drivetrain/Automatic
Transmission/Transaxle/Testing and Inspection/Component Tests and General Diagnostics/2ML70 - Automatic Transmission/Control
Solenoid Valve and Transmission Control Module Assembly Inspection) to verify control solenoid valve assembly condition.
5. Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test (See: Transmission and
Drivetrain/Automatic Transmission/Transaxle/Testing and Inspection/Component Tests and General Diagnostics/2ML70 - Automatic
Transmission/Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test) to verify control solenoid
valve assembly function.
6. Inspect the trans fluid pump ball check valve for possible sticking or damage.
瀚慖f the check ball is stuck or damaged, replace the check ball.
7. Inspect the hybrid direct, 2-3-4 clutch regulator valve for sticking or damage.
瀚慖f you found a concern with the hybrid direct, 2-3-4 clutch regulator valve, repair or replace the valve or valve body.
Monday, September 7, 2020
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 512
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 512
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B1925 02
- Left Seat Cushion Heater Sensor Circuit Shorted to Ground
DTC B1925 05
- Left Seat Cushion Heater Sensor Circuit Shorted to Battery or Open
DTC B2170 02
- Right Seat Heater Cushion Sensor Circuit Shorted to Ground
DTC B2170 05
- Right Seat Heater Cushion Sensor Circuit Shorted to Battery or Open
Diagnostic Fault Information
Circuit/System Description
The heated seat temperature sensor that set this diagnostic trouble code (DTC) is located in the seat cushion just under the seat cover with the seat
heating element. The rear heated seat module (RHSM) supplies a 5 V reference voltage through the temperature sensor signal circuit and a ground
through the low reference circuit to the sensor. The RHSM monitors the voltage of the sensor signal circuit to determine the temperature of the seat.
The temperature sensor varies in resistance based on the temperature of the heating element causing the signal voltage to change. Once the seat
reaches the set temperature, the RHSM will then cycle the control circuit of the heating elements ON and OFF in order to maintain the desired seat
temperature based on the feedback voltage from the sensor.
Conditions for Running the DTC
The RHSM must be powered.
Conditions for Setting the DTC
B1925 02 or B2170 02
The temperature sensor voltage drops below 0.80 V for more than 1 second.
B1925 05 or B2170 05
The temperature sensor voltage is greater than 5 V for more than 1 second.
Action Taken When the DTC Sets
The heated seat function for the affected seat will be disabled.
Conditions for Clearing the DTC
* The current DTC will clear 3 seconds after the reference voltage returns to normal operating range, and the ignition is cycled OFF then back
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B1925 02
- Left Seat Cushion Heater Sensor Circuit Shorted to Ground
DTC B1925 05
- Left Seat Cushion Heater Sensor Circuit Shorted to Battery or Open
DTC B2170 02
- Right Seat Heater Cushion Sensor Circuit Shorted to Ground
DTC B2170 05
- Right Seat Heater Cushion Sensor Circuit Shorted to Battery or Open
Diagnostic Fault Information
Circuit/System Description
The heated seat temperature sensor that set this diagnostic trouble code (DTC) is located in the seat cushion just under the seat cover with the seat
heating element. The rear heated seat module (RHSM) supplies a 5 V reference voltage through the temperature sensor signal circuit and a ground
through the low reference circuit to the sensor. The RHSM monitors the voltage of the sensor signal circuit to determine the temperature of the seat.
The temperature sensor varies in resistance based on the temperature of the heating element causing the signal voltage to change. Once the seat
reaches the set temperature, the RHSM will then cycle the control circuit of the heating elements ON and OFF in order to maintain the desired seat
temperature based on the feedback voltage from the sensor.
Conditions for Running the DTC
The RHSM must be powered.
Conditions for Setting the DTC
B1925 02 or B2170 02
The temperature sensor voltage drops below 0.80 V for more than 1 second.
B1925 05 or B2170 05
The temperature sensor voltage is greater than 5 V for more than 1 second.
Action Taken When the DTC Sets
The heated seat function for the affected seat will be disabled.
Conditions for Clearing the DTC
* The current DTC will clear 3 seconds after the reference voltage returns to normal operating range, and the ignition is cycled OFF then back
Friday, September 4, 2020
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 452
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 452
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B1449 03
- Remote Device Voltage Below Threshold
DTC B1449 07
- Remote Device Voltage Above Threshold
Diagnostic Fault Information
Circuit/System Description
The infrared module is supplied with 10.5 volts from the rear audio/HVAC module when the rear audio system is active. The infrared module is
permanently grounded at G300.
Conditions for Running the DTC
* Ignition ON.
* Battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
The DTC will set when the rear audio/HVAC module detects a short to voltage, short to ground, or an open/high resistance in the infrared module
voltage signal circuit.
Action Taken When the DTC Sets
The rear audio/HVAC module sets the DTC and the infrared module will be disabled.
Conditions for Clearing the DTC
* The condition responsible for setting the DTC no longer exists.
* A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred.
Reference Information
Schematic Reference
Radio/Navigation System Schematics (See: Accessories and Optional Equipment/Diagrams/Electrical Diagrams/Radio/Navigation System
Schematics)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Video Entertainment System Description and Operation (Non-Headrest DVD Systems) (See: Accessories and Optional Equipment/Description
and Operation/Video Entertainment System Description and Operation (Non-Headrest DVD Systems))Video Entertainment System Description
and Operation (Dual Headrest DVD Systems) (See: Accessories and Optional Equipment/Description and Operation/Video Entertainment System
Description and Operation (Dual Headrest DVD Systems))
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B1449 03
- Remote Device Voltage Below Threshold
DTC B1449 07
- Remote Device Voltage Above Threshold
Diagnostic Fault Information
Circuit/System Description
The infrared module is supplied with 10.5 volts from the rear audio/HVAC module when the rear audio system is active. The infrared module is
permanently grounded at G300.
Conditions for Running the DTC
* Ignition ON.
* Battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
The DTC will set when the rear audio/HVAC module detects a short to voltage, short to ground, or an open/high resistance in the infrared module
voltage signal circuit.
Action Taken When the DTC Sets
The rear audio/HVAC module sets the DTC and the infrared module will be disabled.
Conditions for Clearing the DTC
* The condition responsible for setting the DTC no longer exists.
* A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred.
Reference Information
Schematic Reference
Radio/Navigation System Schematics (See: Accessories and Optional Equipment/Diagrams/Electrical Diagrams/Radio/Navigation System
Schematics)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Video Entertainment System Description and Operation (Non-Headrest DVD Systems) (See: Accessories and Optional Equipment/Description
and Operation/Video Entertainment System Description and Operation (Non-Headrest DVD Systems))Video Entertainment System Description
and Operation (Dual Headrest DVD Systems) (See: Accessories and Optional Equipment/Description and Operation/Video Entertainment System
Description and Operation (Dual Headrest DVD Systems))
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Tuesday, August 11, 2020
2010 Cadillac Truck Escalade RWD V8-6.2L Page 3018
2010 Cadillac Truck Escalade RWD V8-6.2L Page 3018
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC U2142 00
- Lost Communication With Yaw Rate Sensor (YRS)
Circuit/System Description
Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating
information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be
exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an
availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the
ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus
serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain
Management/Computers and Control Systems/Information Bus/Description and Operation).
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter module availability has not been received.
Action Taken When the DTC Sets
* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.
* System OFF lamps will illuminate for these systems.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Diagnostic Aids
* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no
associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are
transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically
after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:
- A control module on the data communication circuit was disconnected while the communication circuit is awake.
- Power to one or more modules was interrupted during diagnosis.
- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.
- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.
- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.
These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.
* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between
control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a
control module based only on a history U-code.
* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication
issue.
* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system
inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.
* Use to determine if the module uses high or low speed GMLAN serial data communications.
* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and
the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control
module.
* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,
providing the vehicle is equipped with the control module.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC U2142 00
- Lost Communication With Yaw Rate Sensor (YRS)
Circuit/System Description
Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating
information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be
exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an
availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the
ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus
serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain
Management/Computers and Control Systems/Information Bus/Description and Operation).
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter module availability has not been received.
Action Taken When the DTC Sets
* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.
* System OFF lamps will illuminate for these systems.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Diagnostic Aids
* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no
associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are
transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically
after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:
- A control module on the data communication circuit was disconnected while the communication circuit is awake.
- Power to one or more modules was interrupted during diagnosis.
- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.
- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.
- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.
These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.
* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between
control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a
control module based only on a history U-code.
* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication
issue.
* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system
inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.
* Use to determine if the module uses high or low speed GMLAN serial data communications.
* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and
the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control
module.
* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,
providing the vehicle is equipped with the control module.
Sunday, August 9, 2020
2010 Cadillac Truck Escalade RWD V8-6.2L Page 2961
2010 Cadillac Truck Escalade RWD V8-6.2L Page 2961
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC U2142 00
- Lost Communication With Yaw Rate Sensor (YRS)
Circuit/System Description
Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating
information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be
exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an
availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the
ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus
serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain
Management/Computers and Control Systems/Information Bus/Description and Operation).
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter module availability has not been received.
Action Taken When the DTC Sets
* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.
* System OFF lamps will illuminate for these systems.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Diagnostic Aids
* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no
associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are
transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically
after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:
- A control module on the data communication circuit was disconnected while the communication circuit is awake.
- Power to one or more modules was interrupted during diagnosis.
- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.
- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.
- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.
These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.
* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between
control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a
control module based only on a history U-code.
* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication
issue.
* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system
inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.
* Use to determine if the module uses high or low speed GMLAN serial data communications.
* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and
the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control
module.
* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,
providing the vehicle is equipped with the control module.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC U2142 00
- Lost Communication With Yaw Rate Sensor (YRS)
Circuit/System Description
Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating
information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be
exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an
availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the
ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus
serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain
Management/Computers and Control Systems/Information Bus/Description and Operation).
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter module availability has not been received.
Action Taken When the DTC Sets
* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.
* System OFF lamps will illuminate for these systems.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Diagnostic Aids
* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no
associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are
transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically
after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:
- A control module on the data communication circuit was disconnected while the communication circuit is awake.
- Power to one or more modules was interrupted during diagnosis.
- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.
- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.
- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.
These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.
* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between
control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a
control module based only on a history U-code.
* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication
issue.
* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system
inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.
* Use to determine if the module uses high or low speed GMLAN serial data communications.
* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and
the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control
module.
* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,
providing the vehicle is equipped with the control module.
Thursday, August 6, 2020
2010 Cadillac Truck Escalade RWD V8-6.2L Page 2904
2010 Cadillac Truck Escalade RWD V8-6.2L Page 2904
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC U2142 00
- Lost Communication With Yaw Rate Sensor (YRS)
Circuit/System Description
Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating
information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be
exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an
availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the
ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus
serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain
Management/Computers and Control Systems/Information Bus/Description and Operation).
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter module availability has not been received.
Action Taken When the DTC Sets
* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.
* System OFF lamps will illuminate for these systems.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Diagnostic Aids
* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no
associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are
transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically
after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:
- A control module on the data communication circuit was disconnected while the communication circuit is awake.
- Power to one or more modules was interrupted during diagnosis.
- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.
- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.
- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.
These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.
* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between
control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a
control module based only on a history U-code.
* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication
issue.
* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system
inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.
* Use to determine if the module uses high or low speed GMLAN serial data communications.
* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and
the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control
module.
* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,
providing the vehicle is equipped with the control module.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC U2142 00
- Lost Communication With Yaw Rate Sensor (YRS)
Circuit/System Description
Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating
information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be
exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an
availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the
ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus
serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain
Management/Computers and Control Systems/Information Bus/Description and Operation).
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter module availability has not been received.
Action Taken When the DTC Sets
* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.
* System OFF lamps will illuminate for these systems.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Diagnostic Aids
* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no
associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are
transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically
after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:
- A control module on the data communication circuit was disconnected while the communication circuit is awake.
- Power to one or more modules was interrupted during diagnosis.
- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.
- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.
- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.
These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.
* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between
control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a
control module based only on a history U-code.
* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication
issue.
* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system
inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.
* Use to determine if the module uses high or low speed GMLAN serial data communications.
* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and
the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control
module.
* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,
providing the vehicle is equipped with the control module.
Wednesday, July 22, 2020
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2010 Cadillac Truck Escalade RWD V8-6.2L Page 2535
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P2635
- Fuel Pump Flow Performance
Diagnostic Fault Information
Circuit/System Description
The engine control module (ECM) supplies voltage to the fuel pump control module when the ECM detects that the ignition is on. The voltage from
the ECM to the fuel pump control module remains active for 2 seconds, unless the engine is in crank or run. While this voltage is being received,
the fuel pump control module closes the ground switch of the fuel pump and also supplies a varying voltage to the fuel tank pump module in order
to maintain the desired fuel rail pressure.
Conditions for Running the DTC
* DTC P018B, P018C, P018D, P0231, P0232, P023F, P064A, P1255 or P06A6 are not active.
* DTC P0641 has not failed this ignition cycle.
* Fuel pump control is enabled and the fuel pump control state is normal.
* The system voltage is greater than 11 V.
* The engine has been running for more than 30 seconds.
Conditions for Setting the DTC
This DTC sets when the fuel pump control module detects a predetermined fuel pressure performance degradation between the desired fuel rail
pressure and the current fuel rail pressure.
Action Taken When the DTC Sets
DTC P2635 is a Type B DTC.
Conditions for Clearing the DTC
DTC P2635 is a Type B DTC.
Diagnostic Aids
Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records
can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the
diagnostic test reported a pass and/or a fail.
Reference Information
Schematic Reference
Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Fuel System Description (See: Powertrain Management/Computers and Control Systems/Description and Operation/Fuel System Description)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P2635
- Fuel Pump Flow Performance
Diagnostic Fault Information
Circuit/System Description
The engine control module (ECM) supplies voltage to the fuel pump control module when the ECM detects that the ignition is on. The voltage from
the ECM to the fuel pump control module remains active for 2 seconds, unless the engine is in crank or run. While this voltage is being received,
the fuel pump control module closes the ground switch of the fuel pump and also supplies a varying voltage to the fuel tank pump module in order
to maintain the desired fuel rail pressure.
Conditions for Running the DTC
* DTC P018B, P018C, P018D, P0231, P0232, P023F, P064A, P1255 or P06A6 are not active.
* DTC P0641 has not failed this ignition cycle.
* Fuel pump control is enabled and the fuel pump control state is normal.
* The system voltage is greater than 11 V.
* The engine has been running for more than 30 seconds.
Conditions for Setting the DTC
This DTC sets when the fuel pump control module detects a predetermined fuel pressure performance degradation between the desired fuel rail
pressure and the current fuel rail pressure.
Action Taken When the DTC Sets
DTC P2635 is a Type B DTC.
Conditions for Clearing the DTC
DTC P2635 is a Type B DTC.
Diagnostic Aids
Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records
can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the
diagnostic test reported a pass and/or a fail.
Reference Information
Schematic Reference
Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Fuel System Description (See: Powertrain Management/Computers and Control Systems/Description and Operation/Fuel System Description)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 269
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B251A 01
- All Door Unlatch Circuit Short to Battery
DTC B251A 02
- All Door Unlatch Circuit Short to Ground
DTC B251B 02
- Driver Door Unlatch High Control Circuit Short to Ground
DTC B251B 04
- Driver Door Unlatch High Control Circuit Open
DTC B251C 04
- Passenger Door Unlatch High Control Circuit Open
DTC B251D 04
- Left Rear Door Unlatch High Control Circuit Open
DTC B251E 04
- Right Rear Door Unlatch High Control Circuit Open
Diagnostic Fault Information
Circuit/System Description
The system is designed so that when the operator approaches a locked vehicle with the keyless entry transmitter, the keyless entry control module
will detect the keyless entry transmitter and when an exterior door handle is pulled the keyless entry control module will command all doors to
unlock and the door to unlatch allowing the door to be pulled open.
Conditions for Running the DTC
The system voltage is 9-16 V.
Conditions for Setting the DTC
B251A 01
The keyless entry control module detects a short to voltage on the passenger or left rear or right rear door latch motor unlatch low control circuit.
B251A 02
The keyless entry control module detects a short to ground on the passenger or left rear or right rear door latch motor unlatch low control circuit.
Thursday, March 19, 2020
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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 361
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B396C 08
- Liftgate Mode Switch Circuit Performance Signal Invalid
DTC B396D 02
- Front Liftgate Actuator Switch Circuit Short To Ground
Diagnostic Fault Information
Circuit/System Description
The interior liftgate rotary control switch contains 3 resistors which are in series for the liftgate mode, depending upon which position is selected
will determine which combination of resistors are used. The liftgate module monitors the voltage level in the liftgate mode signal circuit, as each
mode is selected, the voltage within the signal circuit incrementally drops. It is this method the liftgate module will determine if mode switch is in
the manual mode, garage mode or the maximum open mode.
The interior liftgate control switch has of a push button switch to command the liftgate to open and close. The liftgate module monitors the voltage
level on the open/close signal circuit, when the switch is not being pressed the voltage level is at the system voltage. When the switch is pressed a
contact within the interior liftgate control switch closes providing a ground path for the signal circuit causing the voltage level to drop to near zero
volts. The liftgate module will detect the voltage drop and will then command the liftgate to open or close depending upon the current state of the
liftgate at the time the switch is pressed.
Conditions for Running the DTC
The system voltage is 9-16 V.
Conditions for Setting the DTC
B396C 08
The liftgate control module detects an out of range condition in the mode switch signal circuit.
B396D 02
The liftgate control module detects a short to ground in the rear liftgate open/close switch signal circuit for greater than 60 seconds.
Action Taken When the DTC Sets
B396C 08
The manual mode function and the garage mode function will be inoperative.
B396D 02
The liftgate module will ignore the switch input from the interior liftgate control switch and the liftgate operations will only be available from the
liftgate switches located on the liftgate panel or by an open or close request from the remote control keyless entry module.
Conditions for Clearing the DTC
* The DTC will be current for as long as the fault is present.
* When the fault is no longer present, the DTC will be a history DTC.
* A history DTC will clear after 50 ignition cycles.
Diagnostic Aids
* If the liftgate will not release from the closed position, refer to Opening the Liftgate Without Electrical Power (See: Body and Frame/Doors,
Hood and Trunk/Trunk / Liftgate/Service and Repair/Procedures) for the appropriate procedure
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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 210
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions)provides an overview of each diagnostic category.
DTC Descriptors
DTC B125A 02
- Antenna Signal Circuit Short to Ground
DTC B125A 04
- Antenna Signal Circuit Open Circuit
Diagnostic Fault Information
Circuit/System Description
The multi-band antenna is located on the roof of the vehicle. The radio antenna is enabled when the radio is turned on. The radio provides battery
voltage to the antenna using the center conductor of the antenna coaxial cable. When a 12 V signal is seen on the center conductor of the antenna
coax, both AM and FM signals are amplified.
Conditions for Running the DTC
* Ignition ON.
* Battery voltage must be between 9-16 V.
Conditions for Setting the DTC
B125A 02
The radio detects a short to ground in the antenna signal circuit center conductor.
B125A 04
The radio detects an open in the antenna signal circuit center conductor.
Action Taken When the DTC Sets
Radio reception may be poor or not available.
Conditions for Clearing the DTC
* The condition responsible for setting the DTC no longer exists.
* A history DTC will clears after 50 consecutive malfunction-free ignition cycles have occurred.
Reference Information
Schematic Reference
Radio/Navigation System Schematics (See: Accessories and Optional Equipment/Diagrams/Electrical Diagrams/Radio/Navigation System
Schematics)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views/Connector End Views By Name)
Description and Operation
Radio/Audio System Description and Operation (See: Accessories and Optional Equipment/Description and Operation/Radio/Audio System)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 427
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC B1019 00
- System Configuration Error
Circuit/System Description
When calibrating the liftgate position, the liftgate control module is placed in a functional state to learn the liftgate travel limits. DTC B1019 00 will
set automatically as an indicator that the system is in learn mode and not as a fault indicator. Once the travel limits are learned by the liftgate control
module, the liftgate control module will exit calibration mode and DTC B1019 00 become a history code.
Conditions for Running the DTC
The system voltage is 9-18 V.
Conditions for Setting the DTC
Whenever the liftgate control module is replaced or in learn mode.
Action Taken When the DTC Sets
The power liftgate system will be disabled.
Conditions for Clearing the DTC
* The DTC will be current until the liftgate calibration procedure has been completed.
* When the calibration procedure has been completed the DTC will be a history DTC.
Diagnostic Aids
Setting B1019 00 is normal after flashing the liftgate control module. This DTC will be current after flashing and the DTC will go to history after
learning. This is a normal behavior by design and is not necessary to replace the liftgate control module.
Reference Information
Schematic Reference
Liftgate Schematics (See: Body and Frame/Locks/Diagrams/Electrical Diagrams/Liftgate Schematics)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views/Connector End Views By Name)
Description and Operation
Liftgate Description and Operation (See: Body and Frame/Doors, Hood and Trunk/Trunk / Liftgate/Description and Operation/Liftgate)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Testing
Perform the Liftgate Calibration (See: Body and Frame/Doors, Hood and Trunk/Trunk / Liftgate/Testing and Inspection/Programming and
Relearning). The K39 liftgate control module should learn the travel limits, exit the calibration mode, and B1019 00 will become a history code.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 692
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC B3797 02
- All Door Dead Lock Circuit Short to Ground
Diagnostic Fault Information
Circuit/System Description
When the body control module (BCM) receives a command to activate the door dead locks, the BCM will apply voltage to the DOOR LK SEC pcb
relay. This will energize the relay closing the contacts and enable the BCM to supply voltage to the dead locks in each of the doors.
Conditions for Running the DTC
The system voltage must be between 9-16 V.
Conditions for Setting the DTC
The BCM detects a short to ground in the DOOR LK SEC pcb relay control circuit.
Action Taken When the DTC Sets
The dead locks will be inoperative
Conditions for Clearing the DTC
* This DTC will change from current to history when the fault is no longer present.
* A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
Reference Information
Schematic Reference
Door Lock/Indicator Schematics (See: Body and Frame/Locks/Diagrams/Electrical Diagrams/Door Lock/Indicator Schematics)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views/Connector End Views By Name)
Description and Operation
Power Door Locks Description and Operation (See: Body and Frame/Locks/Power Locks/Description and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Verification
Ignition ON, command the Door Deadlock Lock/Unlock to LOCK and UNLOCK with a scan tool. Listen or feel for the operation of the deadlock
actuators performing the LOCK and UNLOCK functions.
Circuit/System Testing
1. Ignition OFF, disconnect the X2 harness connector at the rear fuse block
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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 205
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B0978 01
- Power Mode Accessory Indicator Control Circuit Short to Battery
DTC B0978 02
- Power Mode Accessory Indicator Control Circuit Short to Ground
DTC B0978 04
- Power Mode Accessory Indicator Control Circuit Open
DTC B097B 00
- Power Mode Start Switch Circuit Malfunction
DTC B097B 02
- Power Mode Start Switch Circuit Short to Ground
DTC B097B 04
- Power Mode Start Switch Circuit Open
DTC B097B 08
- Power Mode Start Switch Circuit Performance - Signal Invalid
DTC B097B 61
- Power Mode Start Switch Circuit - Stuck
DTC B097C 01
- Power Mode Run/Start Circuit Indicator Short to Battery
DTC B097C 02
- Power Mode Run/Start Circuit Indicator Short to Ground
DTC B097C 04
- Power Mode Run/Start Indicator Circuit Open
Circuit/System Description
The ignition mode switch has 2 LED's that indicate the vehicle power mode. When the vehicle is in the off mode, both LED's will be off. Pressing
the ignition mode switch button once (without the brake pedal applied), the vehicle enters the accessory mode and the amber LED (ACC) will
illuminate. Pressing the ignition mode switch button a second time (without the brake pedal applied), the vehicle enters the run/start mode (without
the engine running) and the green LED (Run/Start) will illuminate. With the ignition off (with the brake pedal applied), pressing the ignition mode
switch button once, the vehicle will enter run/start mode and the green LED (run/start) will illuminate. This will start the engine. Both LED's have
the voltage supplied from the body control module (BCM). The ignition mode switch sends the ignition mode switch status to the passive entry
passive start module (PEPS) and to the BCM. The PEPS module sends a redundant signal to the BCM with the ignition mode switch status.
Conditions for Running the DTC
Voltage supplied to the module is in the normal operating voltage range of 9-16 V.
Conditions for Setting the DTC
B0978, B097C 01
* The BCM detects a short to battery in the respective indicator control circuit, when the output is active.
* The above condition exists for more than 1 second.
B0978, B097B, B097C 02
* The BCM detects a short to ground in the respective circuit, when the output is inactive.
* The above condition exists for more than 1 second.
B0978, B097B, B097C 04
* The BCM detects an open in the respective circuit, when the output is inactive.
* The above condition exists for more than 1 second.
B097B 00
* The BCM detects a difference between the ignition mode switch voltages to the BCM and PEPS module.
* The above condition exists for more than 1 second.
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2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1014
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0116
- Engine Coolant Temperature (ECT) Sensor Performance
DTC P050C
- Cold Start Engine Coolant Temperature (ECT) Performance
Diagnostic Fault Information
Typical Scan Tool Data
Circuit Description
The engine coolant temperature (ECT) sensor is a variable resistor that measures the temperature of the engine coolant. The engine control module
(ECM) supplies 5 V to the ECT signal circuit and supplies a ground to the low reference circuit. The ECM monitors the mutual performance of the
ECT and the intake air temperature (IAT) signals. The ECM monitors the warm up and cool down behavior of the sensors, after a vehicle driven at
operating temperature is shut down. If the ECM detects that the ECT is not with in a predetermined range of IAT after a long soak, or the ECT and
IAT are not within a range of each other, as compared to a previous cold start, this DTC sets.
The following table illustrates the difference between temperature, resistance, and voltage:
Conditions for Running the DTC
P0116
* Before the ECM can report DTC P0116 failed, DTC P0101 must run and pass.
* DTC P0100, P0101, P0102, P0103, P0117, P0118, P0119, P0335, P0336, or P0338 is not set.
* The engine speed is greater than 1,000 RPM.
* The engine coolant temperature is less than 93掳C (200掳F).
* The ignition was OFF for greater than 5 Hours after the previous engine shut down.
* The accumulated air mass of the previous ignition cycle was greater than 1,500 g.
* The DTC runs once an ignition cycle when the above conditions are met for greater than 35 s.
P050C
* The time after the engine started is greater than 5 s.
* The accumulated air mass of the previous ignition cycle was greater than 4,000 g.
* The engine run time of the previous ignition cycle was greater than 8 min.
* The ECT at the previous engine shut-down is greater than 85掳C (185掳F).
* The ignition was OFF for greater than 6 h after the previous engine shut-down.
* DTCs P0111, P0112, P0113, P0114, P0117 or P0118 are not set.
* The block heater is not detected.
* This DTC runs continuously.
Conditions for Setting the DTC
* The ECM determines the difference between the ECT and IAT at ignition ON is not within 10掳C (50掳F) of the difference recorded during a
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2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 3018
2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 3018
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC U2142 00
- Lost Communication With Yaw Rate Sensor (YRS)
Circuit/System Description
Modules connected to the CAN bus serial data circuits monitor for serial data communications during normal vehicle operation. Operating
information and commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be
exchanged on the serial data circuits. The messages are supervised and also, some periodic messages are used by the receiver module as an
availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
The electronic brake control module (EBCM) activates the other modules connected to the CAN serial data circuits by applying voltage when the
ignition key is in ACC, ON or START. The EBCM, Yaw Rate and Lateral Acceleration Sensor are the only modules connected to the CAN bus
serial data circuits. For more information on CAN bus serial data refer to Data Link Communications Description and Operation (See: Powertrain
Management/Computers and Control Systems/Information Bus/Description and Operation).
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter module availability has not been received.
Action Taken When the DTC Sets
* The vehicle stability enhancement system (VSES), if equipped, and traction control system (TCS) will not function.
* System OFF lamps will illuminate for these systems.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Diagnostic Aids
* Sometimes, while diagnosing a specific customer concern or after a repair, you may notice a history U-code present. However, there is no
associated "current" or "active" status. Loss-of- communication U-codes such as these can set for a variety of reasons. Many times, they are
transparent to the vehicle operator and technician, and/or have no associated symptoms. Eventually, they will erase themselves automatically
after a number of fault-free ignition cycles. This condition would most likely be attributed to one of these scenarios:
- A control module on the data communication circuit was disconnected while the communication circuit is awake.
- Power to one or more modules was interrupted during diagnosis.
- A low battery condition was present, so some control modules stop communicating when battery voltage drops below a certain threshold.
- Battery power was restored to the vehicle and control modules on the communication circuit did not all re-initialize at the same time.
- If a loss-of-communication U-code appears in history for no apparent reason, it is most likely associated with one of the scenarios above.
These are all temporary conditions and should never be interpreted as an intermittent fault, causing you to replace a part.
* A control module may have a U-code stored in history that does not require any repairs. Issues with late or corrupted messages between
control modules can be temporary with no apparent symptom or complaint; this does not mean the control module is faulty. Do not replace a
control module based only on a history U-code.
* Do not replace a control module reporting a U-code. The U-code identifies which control module needs to be diagnosed for a communication
issue.
* Communication may be available between the BCM and the scan tool with either the low or high speed GMLAN serial data system
inoperative. This condition is due to the BCM using both the low and high speed GMLAN systems.
* Use to determine if the module uses high or low speed GMLAN serial data communications.
* Some control modules may not have internal protection for specific control circuits and may open a B+ or ignition fuse. If a fuse is open and
the B+ or ignition circuit is not shorted to ground, ensure none of the control circuits are shorted to ground before replacing the control
module.
* This diagnostic can be used for any control module that is not communicating, regardless of the type of serial data circuit it is connected to,
providing the vehicle is equipped with the control module.
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