2010 Cadillac Truck SRX AWD V6-3.0L Page 244
The HVAC control module detects the sensor signal out of range. The signal voltage is less than 0.1 V or greater than 4.9 V for more than 50 ms.
Action Taken When the DTC Sets
The system operates using a default value.
Conditions for Clearing the DTC
The sensor signal is within specified range between 0.1-4.9 V.
Reference Information
Schematic Reference
HVAC Schematics (See: Heating and Air Conditioning/Diagrams/Electrical Diagrams)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views/Connector End Views By Name)
Description and Operation
Automatic HVAC Description and Operation (See: Heating and Air Conditioning/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
Measure actual temperature using a thermometer at each of the duct temperature sensors. Compare this value to the appropriate scan tool Duct
Actual parameter. The measured temperature should be within 5掳C (9掳F) difference of appropriate Duct Actual parameter value.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the appropriate temperature sensor.
2. Test for less than 10 ohm between the temperature sensor ground circuit terminal B and ground.
瀚慖f greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the K33 HVAC
Control Module.
3. Ignition ON, test for 4.8-5.2 V between the signal circuit terminal A and ground.
瀚慖f less than the specified range, test the signal circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the
K33 HVAC Control Module.
瀚慖f greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K33 HVAC Control
Module.
4. If all circuits test normal, replace the temperature sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* HVAC Component Replacement Reference (See: Heating and Air Conditioning/Service and Repair/Removal and Replacement)
* Control Module References (See: Testing and Inspection/Programming and Relearning)
B0178
DTC B0173, B0178, B0509, B0514, B0519, B3583, or B3933
