Pinpoint Test N: The Ambient Lighting Does Not Cycle Through All Color Combinations

Interior Lighting

Pinpoint Test N: The Ambient Lighting Does Not Cycle Through All Color Combinations

Normal Operation

The Interior Lighting Control Module (ILCM) turns the ambient lighting on to a pre-set color (white) and brightness setting when a door is open or the illuminated entry feature is active. The ambient lighting is also active when the ignition is in the RUN mode and the parking lamps are on.

The ILCM (Interior Lighting Control Module) sends a voltage signal to the ambient lighting switch. When the ambient lighting switch (a momentary contact switch) is pressed to cycle the color setting, the voltage signal is routed to ground, indicating a request for the module to cycle the ambient lighting to the next color setting or to turn the ambient lighting off.

The color and brightness settings can only be changed when the ignition is in the RUN mode, the parking lamps are on and the doors are closed.





This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Ambient lighting harness

- ILCM (Interior Lighting Control Module)

PINPOINT TEST N : THE AMBIENT LIGHTING DOES NOT CYCLE THROUGH ALL COLOR COMBINATIONS

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

N1 CHECK THE INPUT FROM THE AMBIENT LIGHTING SWITCH

- Ignition ON.

- Enter the following diagnostic mode on the scan tool: ILCM (Interior Lighting Control Module) DataLogger.

- While pressing and releasing the ambient lighting switch, monitor the ILCM (Interior Lighting Control Module) ambient lighting switch PID (AmbiColor).

Does the PID read active with the switch pressed and idle with the switch released?

Yes
GO to N2.

No
GO to Pinpoint Test M. Pinpoint Test M: The Ambient Lighting Is Inoperative

N2 CHECK THE AMBIENT LIGHTING HARNESS

- Ignition OFF.

- Check the diode circuits between the ILCM (Interior Lighting Control Module) connector, harness side as follows:

Connector-Pin/Circuit Connector-Pin/Circuit C3256-3 CLN45 (GN) C3256-20 RLN44 (BN) C3256-4 CLN44 (OG) C3256-20 RLN44 (BN) C3256-5 CLN57 (WH) C3256-20 RLN44 (BN) C3256-6 CLN46 (BU) C3256-20 RLN44 (BN)






Does the meter indicate the circuit is good?

Yes
GO to N3.

No
REPAIR the circuit in question or INSTALL a new ambient lighting harness. TEST the system for normal operation.

N3 CHECK FOR CORRECT ILCM (Interior Lighting Control Module) OPERATION

- Disconnect the ILCM (Interior Lighting Control Module) connector.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect the ILCM (Interior Lighting Control Module) connector and make sure it seats correctly.

- Operate the system and verify the concern is still present.

Is the concern still present?

Yes
INSTALL a new ILCM (Interior Lighting Control Module). REFER to Interior Lighting Control Module (ILCM) . 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.