Pinpoint Test D: The Steering Wheel Switch Illumination Is Inoperative

Instrument Cluster and Panel Illumination

Pinpoint Test D: The Steering Wheel Switch Illumination Is Inoperative

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

Normal Operation

The Body Control Module (BCM) sends voltage to the steering wheel switches. The voltage passes through the clockspring to the steering wheel harness and on to the steering wheel switches.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Steering wheel switch(es)

- Steering wheel harness

- Clockspring

PINPOINT TEST D : THE STEERING WHEEL SWITCH 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.

D1 CHECK THE OTHER DIMMABLE LIGHTING SWITCHES

- Ignition OFF.

- Place the headlamp switch in the PARKING LAMPS ON position.

- Press and hold the instrument panel dimmer switch up to the full illumination position and observe other dimmable switches.

Are all the dimmable switches inoperative?

Yes
GO to Pinpoint Test B Pinpoint Test B: All Dimmable Non-Networked Illumination Is Inoperative.

No
GO to D2.

D2 CHECK THE HORN OPERATION

- Press the driver air bag module against the steering wheel.

Does the horn sound?

Yes
GO to D3.

No
REFER to Horn to diagnose the horn is inoperative.

D3 CHECK FOR VOLTAGE TO THE CLOCKSPRING

- Place the headlamp switch in the OFF position.

- Disconnect: Clockspring C218B.

- Place the headlamp switch in the PARKING LAMPS ON position.

- Press and hold the instrument panel dimmer switch up to the full illumination position.

- Measure the voltage between the clockspring C218B-13, circuit CLN04 (BU/BN), harness side and ground.





Is the voltage greater than 10 volts?

Yes
GO to D4.

No
REPAIR circuit CLN04 (BU/BN) for an open. TEST the system for normal operation.

D4 CHECK THE GROUND CIRCUIT TO THE CLOCKSPRING FOR CONTINUITY

- Measure the voltage between the clockspring C218B-13, circuit CLN04 (BU/BN), harness side and the clockspring C218B-15, circuit GD115 (BK/GY), harness side.





Is the voltage greater than 10 volts?

Yes
GO to D5.

No
REPAIR circuit GD115 (BK/GY) for an open. TEST the system for normal operation.

D5 CHECK FOR VOLTAGE TO THE STEERING WHEEL SWITCH

- Connect: Clockspring C218B.

- Place the headlamp switch in the OFF position.

- Remove the driver air bag module.

- Disconnect: Inoperative Steering Wheel Switch.

- Place the headlamp switch in the PARKING LAMPS ON position.

- For the cruise control switch, measure the voltage between the cruise control switch C2999-3, harness side and the cruise control switch C2999-1, harness side.

- For the steering wheel controls switch, measure the voltage between the steering wheel controls switch C2998-3, harness side and the steering wheel controls switch C2998-1, harness side.





Is the voltage greater than 10 volts?

Yes
REPLACE the inoperative steering wheel switch.

For the cruise control switch, REFER to Fire Suppression System.

For the steering wheel controls switch, REFER to Accessories and Optional Equipment
TEST the system for normal operation.

No
GO to D6.

D6 CHECK FOR VOLTAGE TO THE UPPER CLOCKSPRING

- Disconnect: Clockspring C218C.

- Measure the voltage between the clockspring C218C-6, component side and the clockspring C218C-8, component side.





Is the voltage greater than 10 volts?

Yes
INSTALL a new steering wheel. TEST the system for normal operation.

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