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Serial Link External Fault

Test 1:




Test 2 - 4:






SYMPTOM
SERIAL LINK EXTERNAL FAULT

TEST NOTE
The title for the tests will be PCM STATUS FAILURE.

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

SET CONDITION
When the SKREEM does not receive an expected PCI BUS message transmission acknowledgement from the ECM after 3 transmit attempts.

POSSIBLE CAUSES
- Intermittent wiring harness problem
- Wiring harness inspection
- SKREEM/ECM