2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 271
瀚慖f not within the specified range, refer to Ambient / Inside Air Temperature Sensor Circuit Malfunction.
2. Measure actual inside air temperature using a thermometer. Compare this value to the scan tool Inside Air Temp. Sensor parameter and Aux.
Inside Air Temp. parameter. The measured temperature should be within 5 degrees of parameter.
瀚慖f not within the specified range, refer to Ambient / Inside Air Temperature Sensor Circuit Malfunction.
3. 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 degrees of appropriate Duct Actual parameter.
瀚慖f not within the specified range, refer to Duct Temperature Sensor Circuit Malfunction.
Circuit/System Testing
Ambient / Inside Air Temperature Sensor Circuit Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate temperature sensor.
2. Test for less than 1 ohm between the low reference circuit terminal B and ground.
瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the HVAC
control module.
3. Ignition ON, verify the appropriate scan tool Temp Sensor parameter is greater than 85掳C (185掳F).
瀚慖f less than the specified range, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the HVAC
control module.
4. Install a 3-amp fused jumper wire between the signal circuit terminal A and the low reference circuit terminal B. Verify the scan tool Temp
Sensor parameter is less than -35掳C (-39掳F).
瀚慖f greater than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal,
replace the HVAC control module.
5. If all circuits test normal, test or replace the appropriate temperature sensor.
Duct Temperature Sensor Circuit Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate temperature sensor.
2. Test for less than 1.0 ohm between the low reference circuit terminal 2 and ground.
瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the HVAC
control module.
3. Ignition ON, verify the appropriate Duct Temp Sensor Actual parameter is greater than 85掳C (185掳F).
瀚慖f less than the specified range, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the HVAC
control module.
4. Install a 3-amp fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2. Verify the scan tool Duct
Temp Sensor Actual parameter is less than -35掳C (-39掳F).
瀚慖f greater than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal,
replace the HVAC control module.
5. If all circuits test normal, test or replace the appropriate temperature sensor.
Component Testing
1. Ignition OFF, disconnect the harness connector at the appropriate temperature sensor.
2. Test for the appropriate resistance between the signal terminal A or 1 and the low reference terminal B or 2. Refer to Sensor Resistance Table
for Sensor Resistance Table (See: Heating and Air Conditioning/Specifications/Electrical Specifications) resistance values.
瀚慖f not within the specified range, replace the sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Air Temperature Sensor Replacement - Upper Auxiliary (See: Heating and Air Conditioning/Discharge Air Temperature Sensor /
Switch/Service and Repair/Air Temperature Sensor Replacement - Upper Auxiliary)
* Duct Air Temperature Sensor Replacement - Upper Right Side (See: Heating and Air Conditioning/Discharge Air Temperature Sensor /
