2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 801
Procedures/Connector Repairs/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) 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) Wiring Repairs
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) Control Module References for scan tool information
Circuit/System Verification
Ignition ON, observe the scan tool A/C Evaporator Temperature Sensor parameter. The reading should be between -39掳F (-35掳C) and 208掳F (98掳C)
and change with evaporator air temperature changes.
Circuit/System Testing
Important: If the evaporator air temperature sensor has an out of range condition caused by a short to voltage, short to ground, or an
open/high resistance, the scan tool will display the same value: 11掳C (51掳F).
1. Ignition OFF, disconnect the harness connector at the evaporator air temperature sensor.
2. Ignition OFF, test for less than 10 ohms 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, test for 4.8-5.2 volts between the signal circuit terminal 1 and low reference circuit terminal 2.
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
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 HVAC control
module.
4. If all circuits test normal, test or replace the evaporator air temperature sensor.
Component Testing
1. Test the evaporator air temperature sensor by varying the sensor temperature while monitoring the sensor resistance.
2. Compare the readings with the Sensor Resistance Table (See: Heating and Air Conditioning/Specifications/Electrical Specifications) Sensor
Resistance Table and verify that the resistance is within 5 percent of the specification.
瀚慖f not within the specified range, replace the sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) Diagnostic Repair Verification after completing the diagnostic procedure.
* Air Conditioning Refrigerant Temperature Sensor Replacement (See: Heating and Air Conditioning/Refrigerant Temperature
Sensor/Service and Repair/HVAC - Automatic) Evaporator Air Temperature Sensor Replacement
* Control Module References (See: Testing and Inspection/Programming and Relearning) Control Module References for HVAC control
module replacement, setup, and programming
HVAC - Manual
DTC B3933
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.
