Inspection and Verification

Climate Control System

Inspection and Verification

NOTE: Verify the service disconnect plug is correctly inserted and locked into the LOCK position.

1. Verify the customer concern.

2. Visually inspect for obvious signs of mechanical or electrical damage.

Visual Inspection Chart







3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.

4. NOTE: Make sure to use the latest scan tool software release.

If the cause is not visually evident, connect the scan tool to the Data Link Connector (DLC).

5. NOTE: The Vehicle Communication Module (VCM) LED prove-out confirms power and ground from the DLC are provided to the VCM.

If the scan tool does not communication with the VCM:

- check the VCM connection to the vehicle.

- check the scan tool connection to the VCM.

- refer to Information Bus, No Power To The Scan Tool, to diagnose no power to the VCM.

6. If the scan tool does not communicate with the vehicle:
- verify the ignition key is in the ON position.

- verify the scan tool operation with a known good vehicle.

- refer to Information Bus to diagnose no response from the HVAC module, Air Conditioning Compressor Module (ACCM), Instrument Panel Cluster (IPC) or PCM.

7. Carry out the network test.
- If the scan tool responds with no communication from one or more modules, refer to Information Bus.

- If the network test passes, retrieve and record the Continuous Memory Diagnostic Trouble Codes (CMDTCs).

8. Clear the CMDTCs and carry out the self-test diagnostics for the HVAC, ACCM, IPC or PCM.

9. If the HVAC DTCs retrieved are related to the concern, go to the HVAC Module DTC Chart. If the ACCM DTCs retrieved are related to the concern, go to the Air Conditioning Compressor Module (ACCM) DTC Chart. If the PCM DTCs retrieved are related to the concern, go to the PCM DTC Chart. For all other DTCs, refer to Body Control Systems. HVAC Module DTC Chart Air Conditioning Compressor Module (ACCM) DTC Chart PCM DTC Chart

If no DTCs are present, GO to Symptom Chart - Climate Control Systems for the appropriate diagnostic action. Symptom Related Diagnostic Procedures