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No BCM Messages Received (Active)

Test 1:




Test 2:





SYMPTOM
NO BCM MESSAGE RECEIVED (ACTIVE) - MTC

WHEN MONITORED
With the ignition ON.

SET CONDITION
If the A/C-Heater Control Module does not receive the dimming function message from the BCM for more than 5 seconds, then the A/C-Heater Control Module LEDs will default to full brightness and the DTC will set.

POSSIBLE CAUSES
- Additional code(s) present
- A/C - heater control module
- Body control module - no dim message to a/c - heater control module