Diagnostic Test
- VERIFY THE DIAGNOSTIC TROUBLE CODE (DTC) IS ACTIVE NOTE:
Make sure the IOD fuse is installed and the battery is fully charged before proceeding.
- Turn the ignition on.
- With the scan tool, read active DTCs.
Is this DTC active?
Yes
- Refer to U0164-LOST COMMUNICATION WITH A/C HEATER CONTROL (HVAC) MODULE and perform the diagnostic procedure.
No
- Refer to DIAGNOSIS AND TESTING and perform the Stored Lost Communication DTCs diagnostic procedure.