Backlight Dimming RX Failure (Stored) - MTC

Test 1:

SYMPTOM
BACKLIGHT DIMMING RX FAILURE (STORED) - MTC

TEST NOTE
This symptom is diagnosed using the test A/C SWITCH FAULT (STORED) - MTC

WHEN MONITORED
With the ignition on.

SET CONDITION
If the A/C Heater Control does not receive the dimming function message from the Body Control Module (BCM) for more than 5 seconds, then the mode switch status indicators on the A/C Heater Control will default to daytime brightness and the DTC will set.

POSSIBLE CAUSES
- Check for active HVAC DTCs and system tests fault messages
- Old DTC or intermittent wiring problem