Panel Lamps Dimmer Circuit

NOTE:

As part of the exterior lighting fail-safe feature, upon ignition ON all of the panel lamps dimmer circuit lamps will illuminate at full intensity and the exterior park lamps and headlight low beams will illuminate regardless of the multi-function switch control knob and stalk positions if the SCCM microcontroller cannot detect an input from the multi-function switch, or if there is a loss of data bus communication.

CONDITION	POSSIBLE CAUSES	CORRECTION
A SINGLE LAMP DOES NOT ILLUMINATE	1. Ineffective or missing bulb or LED unit.	1. Test and replace the lamp bulb or LED unit if required.
	2. Ineffective ground circuit.	2. Test and repair the open lamp ground circuit if required.
	3. Ineffective feed circuit.	3. Test and repair the open lamp feed circuit if required.
A SINGLE LAMP DOES NOT EXTINGUISH	1. Ineffective feed circuit.	1. Test and repair the shorted lamp feed circuit if required.
ALL LAMPS DO NOT ILLUMINATE	1. Ineffective ground circuit.	1. Test and repair the open lamp ground circuit if required.
	2. Ineffective feed circuit.	2. Test and repair the open lamp feed circuit if required.
	3. Ineffective BCM inputs or outputs.	3. Use a diagnostic scan tool and the appropriate diagnostic information for further BCM diagnosis.
ALL LAMPS ILLUMINATE AT FULL INTENSITY AT IGNITION ON	1. Ineffective dimmer module.	1. Test and replace the dimmer module if required.
	2. Ineffective IPC inputs or outputs.	2. Use a diagnostic scan tool and the appropriate diagnostic information for further IPC diagnosis.
	3. Loss of data bus communication.	3. Use a diagnostic scan tool to test the data bus. Refer to the appropriate diagnostic information.