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 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
- Check for active HVAC DTCs and system tests fault messages
- Stored code(s) test complete