Pinpoint Test C: The Steering Wheel Control Illumination Is Inoperative

Instrument Cluster and Panel Illumination

Pinpoint Tests

Pinpoint Test C: The Steering Wheel Control Illumination Is Inoperative

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 steering wheel controls through circuit CLN04 (BU/BN) to the clockspring. The voltage passes through the clockspring to the steering wheel harness and on to the steering wheel control switches. Ground is supplied through the clockspring on circuit GD143 (BK/VT).

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- Steering wheel harness
- Steering wheel control switch
- Clockspring



PINPOINT TEST C: THE STEERING WHEEL CONTROL ILLUMINATION IS INOPERATIVE

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 CIRCUIT CLN04 (BU/BN) FOR AN OPEN


- Ignition OFF.
- Depower the Supplemental Restraint System (SRS). Refer to Air Bag Systems.
- Disconnect: Clockspring C218a.
- Connect: Negative Battery Cable.
- Place the headlamp switch in the PARKING LAMPS ON position.
- Rotate the instrument panel dimmer switch to the full illumination position.
- Measure the voltage between the clockspring C218a-16, circuit CLN04 (BU/BN), harness side and ground.




- Is the voltage great than 10 volts?

Yes
TURN the parking lamps off. GO to C2.

No
REPAIR the circuit. REPOWER the SRS. REFER to Air Bag Systems. TEST the system for normal operation.

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C2 CHECK CIRCUIT GD143 (BK/VT) FOR AN OPEN


- Disconnect: Negative Battery Cable.
- Measure the resistance between the clockspring C218a-5, circuit GD143 (BK/VT), harness side and ground.




- Is the resistance less than 5 ohms?

Yes
GO to C3.

No
REPAIR the circuit. REPOWER the SRS. REFER to Air Bag Systems. TEST the system for normal operation.

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C3 CHECK THE CLOCKSPRING FOR AN OPEN


- Remove the driver air bag module.
- Disconnect: Upper Clockspring C218b.
- Measure the resistance between the clockspring C218a pin 16, component side and the upper clockspring C218b pin 7, component side.




- Measure the resistance between the clockspring C218a pin 5, component side and the upper clockspring C218b pin 4, component side.




- Are the resistances less than 5 ohms?

Yes
GO to C4.

No
INSTALL a new clockspring. TEST the system for normal operation.

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C4 CHECK THE STEERING WHEEL HARNESS


- Disconnect: Steering Wheel Control Switch C203 and Audio/Climate Control Switch C2208.
- Measure the resistance between the upper clockspring, harness side, and the steering wheel control switch as follows:





- Are the resistances less than 5 ohms?

Yes
INSTALL a new steering wheel control switch. INSTALL the driver air bag module. TEST the system for normal operation.

No
REPAIR or INSTALL a new steering wheel harness. INSTALL the driver air bag module. TEST the system for normal operation.

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