B2558

DTC B2558 Interior Lamp Control Output Short To Battery:

CIRCUIT DESCRIPTION
This circuit controls the interior lighting ground by turning the ground on or off. This is a fault code (both history and current) that gets set in the event of a short to the battery. The short is detected when the interior light output is on.

CONDITIONS FOR SETTING THE DTC
The following conditions must be met:
- The interior lamp relay (internal to the BCM ) is on except for in the following modes:
^ Theater
^ Step dim
- The interior lamp feedback is not present for 0.5 seconds from CKT 156.

ACTION TAKEN WHEN THE DTC SETS
^ Turns off the interior lamp relay.
^ Stores the DTC B2558 in the BCM memory.

CONDITIONS FOR CLEARING THE DTC
^ The fault state is exited upon the program return to a lights off state.
^ Conditions for the fault are no longer present.
^ Use the scan tool.

DIAGNOSTIC AIDS
If the DTC is a history DTC, the problem may be intermittent. Try performing the above tests while wiggling the wiring and connectors. This can often cause the malfunction to appear.

TEST DESCRIPTION
The numbers below refer to the numbers on the diagnostic table.
2. This step determines if a short to battery exists in CKT 156, internal to the body control module (BCM).
3. This step determines if a short to battery exists in CKT 156, between the left IP wiring harness junction block and the BCM.
5. This step determines if a short to battery exists in CKT 156, between the following components:
^ The left IP wiring harness junction block
^ The left courtesy lamp
^ The right courtesy lamp
7. This step determines if a short to battery exists in CKT 156, between the left IP wiring harness junction block and the dome lamp.