Volt

Courtesy Lamps Malfunction

The body control module (BCM) supplies battery voltage to the dome/reading lamps - front and left and right sun visor lamps via the courtesy lamp control circuit. When a sun visor mirror is opened, the switch contact close allowing battery voltage to flow illuminating the respective lamps. The front reading lamps are controlled by individual switches that are activated by the operator when additional cabin lighting is required. In the event that any of these courtesy lamps were to remain illuminated for more than 10 min with the vehicle ON/OFF switch in the OFF position and no doors opened, the BCM will deactivate the courtesy lamp control circuit to prevent total battery discharge.

When the F7DR (interior lamps) fuse is open, both dome lamps, sun visor lamps, reading lamps, and reverse lamps will be inoperative. DTC B2545 will also set for the reverse lamps when the vehicle is placed in the reverse gear.

Schematic Reference

Connector End View Reference

Component Connector End Views

Description and Operation

Interior Lighting Systems Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

1. Vehicle OFF, disconnect the harness connector at the inoperative courtesy lamp.
2. Vehicle OFF, scan tool disconnected, all doors closed, all accessories OFF, and wait 2 minutes. Test for less than 10 Ω between the appropriate ground circuit terminal listed below and ground:

•	E37F Dome/Reading Lamps - Front terminal 6

•	E31L Sun Visor Mirror Lamp - Left terminal B

•	E31R Sun Visor Mirror Lamp - Right terminal B

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

3. Connect a test lamp between the appropriate control circuit terminal listed below and ground:

•	E37F Dome/Reading Lamps - Front terminal 1

•	E31L Sun Visor Mirror Lamp - Left terminal A

•	E31R Sun Visor Mirror Lamp - Right terminal A

4. Vehicle in Service Mode, command the Inadvertent Load ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

⇒	If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module.

⇒	If the test lamp is always OFF, test the control circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the K9 Body Control Module.

5. If all circuits test normal, replace the inoperative courtesy lamp.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.