Pinpoint Test C: An Individual Component Illumination Is Inoperative - Dimmable Illumination

Instrument Cluster and Panel Illumination

Pinpoint Tests

Pinpoint Test C: An Individual Component Illumination Is Inoperative - Dimmable Illumination

Refer to Wiring Diagram Set 71, Cluster and Panel Illumination for schematic and connector information. Diagrams By Number

Normal Operation

The Smart Junction Box (SJB) sends a pulse-width modulated voltage to the dimmable components through circuit VLN04 (VT/GY). Ground for the illumination is supplied through circuits GD116 (BK/VT), GD126 (BK/WH) and GD139 (BK/YE).

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- Floor shifter
- Ambient lighting switch (if equipped)
- Memory set switch (if equipped)
- HVAC module (manual temperature control)
- Message center switch
- Window control switch (MKZ)
- Door lock control switch (MKZ)
- Headlamp switch
- Hazard switch
- Clock
- Luggage compartment lid release switch



PINPOINT TEST C: AN INDIVIDUAL COMPONENT ILLUMINATION IS INOPERATIVE - DIMMABLE ILLUMINATION

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

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery.

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C1 CHECK THE VOLTAGE TO THE ILLUMINATION SOURCE


NOTE: If the headlamp switch is the inoperative source, unplug the headlamp switch connector to measure the illumination circuit voltage. Unplugging the connector causes the SJB to turn the exterior lights on by default for 10 minutes, so it is unnecessary to turn the headlamp switch on.

- Ignition OFF.
- Disconnect: Inoperative Illumination Source.
- With the parking lamps on, rotate the instrument panel dimmer switch to the full illumination position.
- Measure the voltage between the inoperative illumination source, harness side and ground as follows:





- Is the voltage greater than 10 volts?

Yes
For the HVAC module, INSTALL a new HVAC module. REFER to Heating and Air Conditioning. TEST the system for normal operation.

For a door lock control switch, INSTALL a new switch for the one in question. REFER to Locks. TEST the system for normal operation.

For a window control switch, INSTALL a new switch for the one in question. REFER to Windows. TEST the system for normal operation.

For all other components, GO to C2.

No
REPAIR the circuit in question. TEST the system for normal operation.

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C2 CHECK THE ILLUMINATION SOURCE GROUND CIRCUIT FOR AN OPEN


- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the inoperative illumination source, harness side and ground as follows:





- Is the resistance less than 5 ohms?

Yes
INSTALL a new component in question. TEST the system for normal operation.

No
REPAIR the circuit. TEST the system for normal operation.

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