2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 587
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, park lamps ON, vary the interior backlight dimming from low to full bright by using the dimmer switch. The LED on all components
should dim and then become full bright.
Circuit/System Testing
Note: Each component on backlighting control circuit may need to be disconnected to isolate a short to voltage or short to ground. Use the
schematic to identify the following:
* All backlighting components that the vehicle is equipped with
* Component locations on the backlighting dimming control circuit
* Each component's control and ground circuit terminals
1. Ignition OFF, disconnect the harness connector at any component on the interior backlighting control circuit.
2. Scan tool disconnected, interior lamps OFF, doors CLOSED, test for less that 10 Ohms between the ground circuit terminal and ground.
瀚慖f greater than the specified range, test the ground circuit for an open/high resistance.
3. Connect a test lamp between the control circuit terminal and ground.
4. Ignition ON, command the LED Backlight Dimming ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing
between the commanded states.
瀚慖f the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
瀚慖f the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace
the K9 BCM.
5. If all circuits test normal, test or replace the appropriate component.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Refer to the appropriate replacement procedure for the component causing the condition.
* Control Module References (See: Testing and Inspection/Programming and Relearning) for BCM replacement, setup and programming
B2645
DTC B2645
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* 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 B2645 03
- Ambient Light Sensor Circuit Low Voltage
DTC B2645 07
- Ambient Light Sensor Circuit High Voltage
Diagnostic Fault Information
