B11D5

B11D5-00-A/C COOLDOWN TEST PERFORMANCE - EVAP TEMP SENSOR ERROR

For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Evaporator Temperature Sensor is a variable resistor that changes in conjunction with temperature, or otherwise known as a thermistor. The Evaporator Temperature Sensor is located in the HVAC housing downstream of the A/C evaporator. The A/C Heater Module monitors the evaporator temperature by monitoring the voltage change of the Evaporator Temperature Sensor Signal circuit. If the monitored voltage drops below or rises above a predetermined voltage, a Diagnostic Trouble Code (DTC) will set. For further information Evaporator Temperature Sensor - Operation.

- When Monitored:
Whenever an A/C Cooldown Test is performed.

- Set Condition:
The A/C Heater Module detects a circuit malfunction with the Evaporator Temperature Sensor during a Cooldown Test.





Always perform the HVAC Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview.

1. CHECK IF DTC IS ACTIVE
1. Ignition on, engine not running.
2. Using the scan tool, perform an A/C Cooldown Test.
3. Using the scan tool, read HVAC DTCs.

Is this DTC active?

Yes

- Go To 2

No

- Go To 4

2. PERFORM HVAC ACTUATOR CALIBRATION TEST
1. Using the scan tool, perform the HVAC Actuator Calibration Test.

Did any other HVAC DTCs set while performing the Actuator Calibration Test?

Yes

- Testing and Inspection Perform the appropriate diagnostic procedure.

No

- Go To 3

3. CHECK THE EVAPORATOR TEMPERATURE SENSOR
1. Replace the Evaporator Temperature Sensor. Evaporator Temperature Sensor - Removal.
2. Using the scan tool, erase HVAC DTCs.
3. Cycle the ignition off for 30 seconds then back on.
4. Using the scan tool, perform an A/C Cooldown Test.
5. With the scan tool, read HVAC DTCs.

Does this DTC reset?

Yes

- Replace and program the A/C Heater Module. A/C And Heater Control Module - Removal.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Test complete.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

4. CHECK THE WIRING AND CONNECTORS
1. The conditions necessary to set the DTC are not present at this time.
2. Using the scan tool, check the Environmental Data to help identify the conditions in which the DTC was set.
3. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
4. Wiggle the wiring and connectors while checking for shorted and open circuits.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the HVAC VERIFICATION TEST. HVAC Verification Test.

No

- Test complete.