Dimming Level Switch Input Circuit Low

Monitored & Set Condition

When Monitored: With ignition On.
Set Condition: The BCM detects a voltage less than .25-volt on the dimming level switch input for more than 5 seconds.

Possible Causes:

Intermittent Conditions
Panel Lamps Dimmer Switch MUX Open
Panel Lamps Dimmer Switch MUX Circuit Short To Ground
Multifunction Switch
Body Control Module

Testing

Turn the ignition on. With the DRBIII(R), clear all BCM DTC's. Actuate the Dimming Level Switch. With the DRBIII(R), read the DTC information. Does the DRBIII(R) read: Dimming Level Switch Input CKT Low? If yes, go to next step. If no, the condition that caused the symptom is currently not present. Inspect the related wiring for a possible intermittent condition. Look for any chafed, pierced, pinched, or partially broken wires. Perform BODY VERIFICATION TEST .
Turn the ignition off. Disconnect the BCM C2 harness connector. Cycle the ignition switch off than back on. Did any of the Courtesy Lamps come on? If yes, go to next step. If no, repair the Panel Lamps Dimmer Switch MUX for an open condition. Perform BODY VERIFICATION TEST .
Ensure the Junction Block C24 harness connector on the front of the junction block is connected. Turn on all overhead, map and rear reading lamps by their own individual switches. This will disconnect each lamp from the Courtesy Lamp Driver Circuit. Did any lamp fail to light when it was turned on by it's own switch? If yes, repair the Panel Lamps Dimmer Switch MUX circuit for a short to ground condition. Perform BODY VERIFICATION TEST . If no, go to next step.
Turn the ignition off. Disconnect the Junction Block C24 harness connector from the front of the junction block. Remove the Body Control Module from the junction block. Measure the voltage of the Courtesy Lamps Driver circuit. Is voltage present on the Courtesy Lamps Driver Circuit? If yes, replace the Multifunction Switch. Perform BODY VERIFICATION TEST . If no, replace the Body Control Module. Perform BODY VERIFICATION TEST .