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Loopback Test Failure

LOOPBACK TEST FAILURE

WHEN MONITORED
When executing an internal loopback 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 loopback test. This DTC will set if the internal loopback test fails.

POSSIBLE CAUSES
- A/C heater control

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 for stored DTC test procedures. HVAC System Test

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