HVAC, ATC

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

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

Theory of Operation

After the initial installation of the A/C Heater Control, the controller is calibrated to each individual blend/mode door actuator. These calibrations are stored as in the number of pulses it takes to move the door from one stop to another. The A/C Heater Control drives the Door Actuators by the use of Door Driver circuit and a Common Door Driver circuit and monitors all door actuator pulses to detect door movement in both directions. Most of the door actuators share a common door driver circuit but each door actuator has its own unique driver circuit. Due to shared circuitry, similar Diagnostic Trouble Codes (DTCs) can set at the same time for multiple actuators depending upon the type of circuit malfunction, its location, and the direction the actuator is moving when the malfunction is present.

- When Monitored:
Whenever a Cooldown Test is performed.

- Set Condition:
The A/C Heater Control 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. Front 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 Control. A/C And Heater Control - 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.