Pinpoint Test B: The Steering Wheel Control Illumination Is Inoperative

Instrument Cluster and Panel Illumination

Pinpoint Tests

Pinpoint Test B: 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 VLN04 (VT/GY) to the clockspring. The voltage passes through the clockspring to circuit VLN04 (VT/GY) to the control switches. Ground to the clockspring is supplied through circuit GD116 (BK/VT). Ground from the clockspring to the steering wheel switch is supplied through circuit GD165 (BK).

This pinpoint test is intended to diagnose the following:

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



PINPOINT TEST B: 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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B1 CHECK CIRCUIT VLN04 (VT/GY) FOR AN OPEN


- Depower the Supplemental Restraint System (SRS). Refer to Air Bag Systems.
- Disconnect: Clockspring C218a.
- Connect: Negative Battery Cable.
- Ignition ON.
- With the parking lamps on, rotate the instrument panel dimmer switch to the full illumination position.
- Measure the voltage between the clockspring C218a-16, circuit VLN04 (VT/GY), harness side and ground.




- Is the voltage greater than 10 volts?

Yes
TURN the parking lamps off. GO to B2 .

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

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B2 CHECK CIRCUIT GD116 (BK/VT) FOR AN OPEN


- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the clockspring C218a-7, circuit GD116 (BK/VT), harness side and ground.




- Is the resistance less than 5 ohms?

Yes
GO to B3.

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

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B3 CHECK THE CLOCKSPRING FOR AN OPEN


- Remove the driver air bag module. Refer to Air Bag Systems.
- Disconnect: Upper Clockspring Connector C218b.
- Measure the resistance between the clockspring C218a pin 16, component side and the upper clockspring connector C218b pin 7, component side.




- Measure the resistance between the clockspring C218a pin 7, component side and the upper clockspring connector C218b pin 2, component side.




- Are the resistances less than 5 ohms?

Yes
GO to B4.

No
INSTALL a new clockspring. INSTALL the driver air bag module. REFER to Air Bag Systems. TEST the system for normal operation.

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B4 CHECK THE STEERING WHEEL HARNESS CIRCUIT VLN04 (VT/GY) FOR AN OPEN


- Disconnect: Steering Wheel Switch C2998 and C2999.
- Measure the resistance between the upper clockspring connector C218b-7, circuit VLN04 (VT/GY), harness side and the steering wheel switch C2998-2, circuit VLN04 (VT/GY), harness side; and between the upper clockspring connector C218b-7, circuit VLN04 (VT/GY), harness side and the steering wheel switch C2999-1, circuit VLN04 (VT/GY), harness side.




- Are the resistances less than 5 ohms?

Yes
GO to B5.

No
REPAIR the circuit. INSTALL the driver air bag module. REFER to Air Bag Systems. TEST the system for normal operation.

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B5 CHECK CIRCUIT GD165 (BK) FOR AN OPEN


- Measure the resistance between the clockspring C218b-2, circuit GD165 (BK), harness side and the steering wheel switch C2998-4, circuit GD165 (BK), harness side; and between the clockspring C218b-2, circuit GD165 (BK), harness side and the steering wheel switch C2999-3, circuit GD165 (BK), harness side.




- Are the resistances less than 5 ohms?

Yes
INSTALL a new speed control switch or audio steering wheel controls as necessary. REFER to Cruise Control or Radio, Stereo and Compact Disc as necessary. INSTALL the driver air bag module. REFER to Air Bag Systems. TEST the system for normal operation.

No
REPAIR the circuit. INSTALL the driver air bag module. REFER to Air Bag Systems. TEST the system for normal operation.

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