Pinpoint Test N: The Ambient Lighting Does Not Cycle Through Brightness Settings
Interior Lighting
Pinpoint Test N: The Ambient Lighting Does Not Cycle Through Brightness Settings
Normal Operation
The Interior Lighting Control Module (ILCM) sends a reference signal to the ambient light switch to monitor for a request to change the brightness level. When the switch for the brightness level is pressed, the signal is routed to ground indicating a request to change the brightness level to the next setting.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Ambient lighting harness
- Ambient lighting switch
- ILCM (Interior Lighting Control Module)
PINPOINT TEST N : THE AMBIENT LIGHTING DOES NOT CYCLE THROUGH BRIGHTNESS SETTINGS
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 (AmbiDim).
Does the PID agree with the switch positions?
Yes
GO to N6.
No
If the PID indicates active with the switch not pressed, GO to N2.
If the PID indicates idle when the switch is pressed, GO to N4.
N2 CHECK THE AMBIENT LIGHTING SWITCH FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: Ambient Lighting Switch C2304.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: ILCM (Interior Lighting Control Module) DataLogger.
- Monitor the ILCM (Interior Lighting Control Module) ambient lighting switch PID (AmbiDim).
Does the PID still read active?
Yes
GO to N3.
No
INSTALL a new ambient lighting switch. REFER to Ambient Lighting Switch . TEST the system for normal operation.
N3 CHECK THE AMBIENT LIGHTING SWITCH INPUT CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: ILCM (Interior Lighting Control Module) C2411.
- Measure the resistance between the ILCM (Interior Lighting Control Module) C2411-9, circuit CLN55 (YE/VT), harness side and ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to N6.
No
REPAIR circuit CLN55 (YE/VT) for a short to ground. CLEAR the DTCs. REPEAT the self-test.
N4 CHECK THE AMBIENT LIGHTING SWITCH INPUT AND GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: ILCM (Interior Lighting Control Module) C2411.
- Disconnect: Ambient Lighting Switch C2304.
- Measure the resistance between the ambient lighting switch C2304-3, circuit CLN55 (YE/VT), harness side and the ILCM (Interior Lighting Control Module) C2411-9, circuit CLN55 (YE/VT), harness side; and between the ambient lighting switch C2304-4, circuit GD114 (BK/BU), harness side and ground.
Are the resistances less than 5 ohms?
Yes
GO to N5.
No
REPAIR circuit CLN55 (YE/VT) or circuit GD114 (BK/BU) for an open. TEST the system for normal operation.
N5 BYPASS THE AMBIENT LIGHTING SWITCH
- Connect: ILCM (Interior Lighting Control Module) C2411.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: ILCM (Interior Lighting Control Module) DataLogger.
- Monitor the ILCM (Interior Lighting Control Module) ambient lighting switch PID (AmbiDim).
- Connect and remove a fused jumper wire between the ambient lighting switch C2304-3, circuit CLN55 (YE/VT), harness side and the ambient lighting switch C2304-4, circuit GD114 (BK/BU), harness side.
Does the PID indicate active?
Yes
INSTALL a new ambient lighting switch. REFER to Ambient Lighting Switch . TEST the system for normal operation.
No
GO to N6.
N6 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.