Diagnostic Routine K

Diagnostic Routine K

Diagnostic Overview

The Interior Courtesy Lamps Stay On Continuously

Refer to Wiring Diagram Set 89 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

REFER to Courtesy Lamps .

DTC Fault Trigger Conditions






Visual Inspection and Diagnostic Pre-checks

- Inspect the interior lamps and make sure the map lamps are not on and the courtesy lamps are not on from the front/driver interior lamp.

Pinpoint Test

1. CHECK THE DOOR AND LIFTGATE AJAR SWITCH PIDs (Parameter Identifications)

1. Ignition ON.

2. Using a scan tool, monitor the BCM (Body Control Module) PIDs (Parameter Identifications).

3. Monitor the BCM (Body Control Module) DOOR_SW_LR, DOOR_SW_PSGR, DOOR_SW_LR and DOOR_SW_RR PIDs (Parameter Identifications) while opening and closing all the doors.

Do all the door ajar switch PID (Parameter Identification) values agree with the door and liftgate positions?







2. CHECK THE FLOOR LAMP GROUND CONTROL CIRCUIT FOR A SHORT TO GROUND

1. Ignition OFF.

2. Disconnect: BCM (Body Control Module) C2280C.

3. Ignition ON.

Do the floor courtesy lamps continue to illuminate?







3. ISOLATE THE BCM (Body Control Module)

1. Ignition OFF.

2. Disconnect: BCM (Body Control Module) C2280H.

3. Ignition ON.

Do the interior courtesy lamps continue to illuminate?







4. CHECK THE INTERIOR COURTESY LAMP GROUND CONTROLLED CIRCUIT FOR A SHORT TO GROUND

1. Ignition OFF.

2. Disconnect: Front Interior Lamp C931 (vehicles without a roof opening panel).

3. Disconnect: Driver Interior Lamp C908 (vehicles with a roof opening panel).

4. For a front interior lamp, measure:





5. For a driver interior lamp, measure:





Is the resistance greater than 10,000 ohms?







5. CHECK FOR CORRECT BCM (Body Control Module) OPERATION

1. Disconnect the BCM (Body Control Module) connectors.

2. Repair:

- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install terminals/pins
- pushed-out pins - install new pins as necessary

3. Reconnect the BCM (Body Control Module) connectors and make sure they seat and latch correctly.

4. Operate the system and determine if the concern is still present.

Is the concern still present?