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Pinpoint Test C: The Courtesy Lamps Stay On Continuously




Interior Lighting

Pinpoint Tests

Pinpoint Test C: The Courtesy Lamps Stay On Continuously

Refer to Wiring Diagram Set 89, Interior Lamps for schematic and connector information. Diagrams By Number

Normal Operation

The Driver Door Module (DDM) monitors the door ajar switch status for each door. When a door is open, the DDM signals the Lighting Control Module (LCM) to supply power to the courtesy lamps. The LCM also monitors the dome lamp switch status from the instrument panel dimmer switch. When the LCM recognizes that the dome lamps have been requested, the LCM supplies power to the courtesy lamps.

- DTC B1322 (Driver Door Ajar Circuit Short to Ground) - an on-demand DTC sets when the DDM senses a short to ground from the driver door ajar input circuit.
- DTC B1566 (Door Ajar Circuit Short to Ground) - an on-demand DTC sets when the DDM senses a short to ground from any of the passenger door ajar inputs circuit.
- DTC B1688 (Lamp Dome Input Circuit Short to Ground) - an on-demand DTC sets when the LCM senses a short to ground from the dome lamp switch input circuit.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- Door ajar switch
- Instrument panel dimmer switch
- DDM
- LCM

PINPOINT TEST C: THE COURTESY LAMPS STAY ON CONTINUOUSLY

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C1 CHECK THE DOOR AJAR PID STATUS WITH THE SCAN TOOL


- Ignition ON.
- Close all the doors.
- Enter the following diagnostic mode on the scan tool: DDM DataLogger.
- Monitor the DDM door ajar PIDs (D_DR_SW and P_DR_SW).
- Do the door ajar PIDs match the door positions?

Yes
GO to C8.

No
For the LH front door, GO to C2. For the RH front, RH or LH rear door, GO to C4.

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C2 CHECK THE LH FRONT DOOR AJAR SWITCH FOR A SHORT TO GROUND


- Disconnect: LH Front Door Ajar Switch C526a.
- Enter the following diagnostic mode on the scan tool: DDM DataLogger.
- Monitor the DDM LH front door ajar PID (D_DR_SW).
- Did the door ajar PID change with the switch disconnected?

Yes
INSTALL a new door ajar switch. REFER to Handles, Locks, Latches and Entry Systems Door Ajar Switch - Front. CLEAR the DTCs. REPEAT the self-test.

No
GO to C3.

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C3 CHECK THE LH FRONT DOOR AJAR SWITCH SIGNAL CIRCUIT FOR A SHORT TO GROUND


- Ignition OFF.
- Disconnect: DDM C501a.
- Measure the resistance between the DDM C501a-22, circuit 867 (DB), harness side and ground.




- Is the resistance greater than 10,000 ohms?

Yes
GO to C12.

No
REPAIR circuit 867 (DB) for a short to ground. CLEAR the DTCs. REPEAT the self-test.

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C4 CHECK THE RH FRONT DOOR AJAR SWITCH FOR A SHORT TO GROUND


- Disconnect: RH Front Door Ajar Switch C602a.
- Enter the following diagnostic mode on the scan tool: DDM DataLogger.
- Monitor the DDM door ajar PID (P_DR_SW).
- Did the door ajar PID change with the switch disconnected?

Yes
INSTALL a new door ajar switch. REFER to Handles, Locks, Latches and Entry Systems Door Ajar Switch - Front. CLEAR the DTCs. REPEAT the self-test.

No
GO to C5.

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C5 CHECK THE RH REAR DOOR AJAR SWITCH FOR A SHORT TO GROUND


- Disconnect: RH Rear Door Ajar Switch C820a.
- Enter the following diagnostic mode on the scan tool: DDM DataLogger.
- Monitor the DDM door ajar PID (P_DR_SW).
- Did the door ajar PID change with the switch disconnected?

Yes
INSTALL a new door ajar switch. REFER to Handles, Locks, Latches and Entry Systems Door Ajar Switch - Rear Door. CLEAR the DTCs. REPEAT the self-test.

No
GO to C6.

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C6 CHECK THE LH REAR DOOR AJAR SWITCH FOR A SHORT TO GROUND


- Disconnect: LH Rear Door Ajar Switch C715a.
- Enter the following diagnostic mode on the scan tool: DDM DataLogger.
- Monitor the DDM door ajar PID (P_DR_SW).
- Did the door ajar PID change with the switch disconnected?

Yes
INSTALL a new door ajar switch. REFER to Handles, Locks, Latches and Entry Systems Door Ajar Switch - Rear Door. CLEAR the DTCs. REPEAT the self-test.

No
GO to C7.

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C7 CHECK THE RH FRONT DOOR AJAR SWITCH SIGNAL CIRCUIT FOR A SHORT TO GROUND


- Ignition OFF.
- Disconnect: DDM C501b.
- Measure the resistance between the DDM C501b-7, circuit 627 (BK/OG), harness side and ground.




- Is the resistance greater than 10,000 ohms?

Yes
GO to C12.

No
REPAIR circuit 627 (BK/OG) for a short to ground. CLEAR the DTCs. REPEAT the self-test.

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C8 CHECK THE INSTRUMENT PANEL DIMMER SWITCH


- Ignition OFF.
- Disconnect: Instrument Panel Dimmer Switch C205b.

- NOTE: Make sure the doors are closed.

- Observe the courtesy lamps.
- Are the courtesy lamps still illuminated?

Yes
GO to C9.

No
INSTALL a new instrument panel dimmer switch. REFER to Instrument Cluster and Panel Illumination Service and Repair. CLEAR the DTCs. REPEAT the self-test.

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C9 CHECK THE HEADLAMP SWITCH INPUT CIRCUIT FOR A SHORT TO GROUND


- Disconnect: LCM C2145b.
- Measure the resistance between the instrument panel dimmer switch C205b-5, circuit 1034 (BK/WH), harness side and ground.




- Is the resistance greater than 10,000 ohms?

Yes
GO to C10.

No
REPAIR circuit 1034 (BK/WH) for a short to ground. CLEAR the DTCs. REPEAT the self-test.

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C10 CHECK THE COURTESY LAMP INPUT CIRCUIT FOR A SHORT TO VOLTAGE


- Disconnect: LCM C2145c.
- Observe the courtesy lamps.
- Are the courtesy lamps still illuminated?

Yes
REPAIR circuit 53 (BK/LB) for a short to voltage. TEST the system for normal operation.

No
GO to C11.

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C11 CHECK FOR CORRECT LCM OPERATION


- Disconnect all the LCM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the LCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?

Yes
INSTALL a new LCM. REFER to Multifunction Electronic Modules Service and Repair. TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

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C12 CHECK FOR CORRECT DDM OPERATION


- Disconnect all the DDM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the DDM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?

Yes
INSTALL a new DDM. REFER to Multifunction Electronic Modules Service and Repair. TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.

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