2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 156
7. Test for less than 5 ohm between the K33 HVAC Control Module signal circuit terminal 5 X2 and signal circuit terminal 4 X1 at the E40
Electrical Auxiliary Heater harness connector.
瀚慖f greater than the specified value, test the circuit for an open/high resistance.
8. If all circuits test normal, replace the E40 Electrical Auxiliary Heater and verify the DTC does not reset.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
Control Module References (See: Testing and Inspection/Programming and Relearning) for HVAC control module replacement, setup, and
programming
B048F
DTC B018A, B048C, B048F, or B1395
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 B018A 02
- Windshield Temperature Sensor Circuit Short to Ground
DTC B018A 05
- Windshield Temperature Sensor Circuit High Voltage/Open
DTC B048C 02
- Humidity Sensor Humidity Circuit Short to Ground
DTC B048C 05
- Humidity Sensor Humidity Circuit High Voltage/Open
DTC B048F 02
- Humidity Sensor Temperature Circuit Short to Ground
DTC B048F 05
- Humidity Sensor Temperature Circuit High Voltage/Open
DTC B1395 03
- Control Module Voltage Reference Output Circuit Low Voltage
DTC B1395 07
- Control Module Voltage Reference Output Circuit High Voltage
Circuit/System Description
The windshield temperature and inside moisture sensor includes the relative humidity sensor, windshield temperature sensor and humidity sensing
element temperature sensor.
This sensor assembly provides information about:
* Relative humidity level at windshield inside
* Temperature of the windshield inside
* Temperature of the humidity sensor element
The relative humidity sensor measures the relative humidity of the compartment side of the windshield. It also detects the temperature of the
windshield surface on the compartment side. Both values are used as control inputs for the HVAC control module application to calculate the fog
risk on windshield compartment side and ability to reduce fuel consumption by decreasing A/C compressor power to a minimum without causing
any fog. The sensor will also enable partial recirculation mode in order to improve heat-up performance of the passenger compartment under cold
ambient temperature conditions without the risk of mist build-up on the windshield. The humidity sensor element temperature sensor supplies the
