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Procedures






STANDARD PROCEDURE - CLOCKSPRING CENTERING

WARNING: To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbag, seat belt tensioner, impact sensor or instrument panel component diagnosis or service. Disconnect and isolate the battery negative (ground) cable, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to take the proper precautions could result in accidental airbag deployment.

CAUTION: Always turn the steering wheel until the front wheels are in the straight-ahead position. Then, prior to disconnecting the steering column from the steering gear, lock the steering wheel to the steering column. If clockspring centering has been compromised for ANY reason, the entire Steering Column Control Module (SCCM) and clockspring unit MUST be replaced with a new unit.





Like the clockspring in a timepiece, the clockspring tape has travel limits and can be damaged by being wound too tightly during full stop-to-stop steering wheel rotation. To prevent this from occurring, the clockspring is centered when it is installed on the steering column. Centering the clockspring indexes the clockspring tape to the movable steering components so that the tape can operate within its designed travel limits. However, if the steering shaft is disconnected from the steering gear, the clockspring rotor spool can change position relative to the fixed steering components. This clockspring has no provisions for re-centering.

The service replacement SCCM is shipped with the clockspring (1) pre-centered and with a red plastic locking pin (2) installed. This locking pin should not be removed until the SCCM has been properly installed on the steering column. If the locking pin is removed before the SCCM is installed on a steering column, clockspring centering may become compromised. The locking pin is removed by rotating it in a clockwise direction, breaking it off in the SCCM housing. Do not bend the locking pin to break it off as this may damage the SCCM housing.

In addition, this clockspring is equipped with a spring activated locking ring (3) that automatically extends to lock the clockspring rotor spool to the SCCM housing as soon as the steering wheel is removed. However, if the locking ring is manually compressed while the clockspring is removed from the steering column, clockspring centering may be compromised. When the steering wheel is properly installed onto the steering column, the locking ring is automatically compressed to unlock the clockspring rotor spool.