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Rolling Code Failure

Test 1:




Test 2-4:






SYMPTOM
ROLLING CODE FAILURE

WHEN MONITORED
At ignition on, after ignition on during any rolling code handshake that occurs with the ECM due to a SKREEM or ECM reset.

SET CONDITION
When a PCM STATUS message with a Valid Key status is not received by the SKREEM within 3.5 seconds of transmitting the last Valid Key Code message to the ECM.

POSSIBLE CAUSES
- Verifying ECM VIN
- Replace SKREEM and check DTC's
- Intermittent wiring harness problem
- ECM