Loopback Test Failure (Active)

LOOPBACK TEST FAILURE (ACTIVE)

For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
When the A/C - Heater Control Module executes an internal loopback test.

- Set Condition:
If the A/C - Heater Control Module fails to send a message, or none of the expected messages arrive for 5 seconds, an internal loopback test is executed. If the internal loopback test fails, the DTC will set.





Diagnostic Test

1. CHECK FOR ADDITIONAL HVAC DTCS
Turn the ignition on.
With the scan tool, read HVAC DTCs.
Does the scan tool display additional HVAC DTCs?

Yes

- Diagnose and repair the DTC(s).
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Replace the A/C - Heater Control Module.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.