Courtesy Lamps Stay On At All Times

Possible Causes:

• Courtesy Lamps Driver Headliner Circuit Short To Ground
• Courtesy Lamps Driver Circuit Body Harness Short To Ground
• Panel Lamps Dimmer Switch MUX Short To Ground
• Multifunction Switch
• Body Control Module

Testing

1. Ensure the Dimmer Switch is off. Close all the passenger doors. Disconnect the Junction Block C24 connector from the front of the junction block. Observe the Courtesy Lamps. Did the Courtesy Lamps turn off? If yes, repair the Courtesy Lamps Driver circuit in the headliner harness for a short to ground. Perform BODY VERIFICATION TEST  . If no, go to next step.
2. Ensure the Dimmer Switch is off. Close all the passenger doors. Disconnect the Junction Block C24 harness connector from the Junction Block. Observe the Courtesy Lamps. Did Courtesy Lamps turn off? If yes, repair the Courtesy Lamps Driver circuit in the Body Harness for a short to ground. Perform BODY VERIFICATION TEST  . If no, go to next step.
3. Disconnect the Body Control Module C2 connector. Disconnect the Multifunction Switch harness connector. Measure the resistance of the Panel Lamps Dimmer Switch MUX circuit to ground. Is the resistance below 5.0 ohms? 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.
4. Turn the ignition off. Disconnect the Body Control Module C2 connector. Disconnect the Multifunction Switch harness connector. Turn the ignition on. Measure the resistance of the Multifunction Switch Ground circuit. Is the resistance below 5.0 ohms? If yes, replace the Multifunction Switch. Perform BODY VERIFICATION TEST  . If no, replace the Body Control Module. Perform BODY VERIFICATION TEST  .