Loopback Test Failure (MTC)

LOOPBACK TEST FAILURE (MTC)

For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
When the A/C Heater Control executes an internal loop-back test.

- Set Condition:
If the A/C Heater Control either fails to broadcast a message on the PCI Bus or fails to receive expected messages from the PCI Bus for 5 seconds it will execute an internal loop-back test. This DTC will set if the internal loop-back test fails.





NOTE: This DTC must be active for the results of this test to be valid. Do not perform this test if this DTC is stored. Refer to HVAC System Test (MTC) for stored DTC test procedures.

Diagnostic Test

1. REPLACE THE A/C HEATER CONTROL


Repair

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