Within the plastic case is a spool-like molded plastic
rotor with a large exposed hub. The upper surface of
the rotor hub has a large, keyed center hole, an index
hole, two short pigtail wires with connectors, and one
connector receptacle that face toward the steering
wheel. Wound around the rotor spool within the case
is a long ribbon-like tape that consists of several thin
copper wire leads sandwiched between two thin plas-
tic membranes. The outer end of the tape terminates
at the connector receptacles that face the instrument
panel, while the inner end of the tape terminates at
the pigtail wires and connector receptacles on the hub
of the clockspring rotor that face the steering wheel.
The lower surface of the rotor hub has a molded plas-
tic turn signal cancel cam with two lobes that is keyed
to the clockspring rotor.
The service replacement clockspring is shipped with the clockspring pre-centered and with a molded plastic locking
pin installed. The locking pin secures the centered clockspring rotor during shipment and handling, but must be
removed after the SCCM is installed on the steering column and after the steering wheel is installed (Refer to 8 -
ELECTRICAL/RESTRAINTS/CLOCKSPRING - STANDARD PROCEDURE - CLOCKSPRING CENTERING).
The clockspring cannot be repaired. If the clockspring is faulty, damaged, or if the driver airbag has been deployed,
the clockspring must be replaced. (Refer to 19 - STEERING/COLUMN/STEERING COLUMN CONTROL MODULE
- REMOVAL).
OPERATION
The clockspring is a mechanical electrical circuit component that is used to provide continuous electrical continuity
between the instrument panel wire harness and certain electrical components mounted on or in the rotating steering
wheel and steering column. The rotating electrical components include the driver airbag, horn switch, and speed
control switch, if the vehicle is so equipped. The clockspring is positioned and secured near the top of the steering
column. The electrical connector on the back of the clockspring case connect the clockspring to the vehicle elec-
trical system through two connectors from the instrument panel wire harness.
The turn signal cancel cam is keyed so as to move with the rotation of the steering column shaft and the steering
wheel. The cancel cam is secured and also keyed to the lower surface of the clockspring rotor hub, which indexes
the clockspring rotor to the turn signal cancel cam. Two short, sleeved pigtail wires on the upper surface of the
clockspring rotor connect the clockspring to the driver airbag.
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 clockspring is
removed from the steering column or if the steering shaft is disconnected from the steering gear, the clockspring
spool can change position relative to the other steering components. The clockspring must be re-centered following
completion of this service or the tape may be damaged.
Service replacement clocksprings are shipped pre-centered and with a locking pin installed. This locking pin should
not be removed until the clockspring has been installed on the steering column and the steering wheel is installed
(Refer to 19 - STEERING/COLUMN/STEERING WHEEL - INSTALLATION). If the locking pin is removed before the
clockspring is installed on a steering column, the clockspring centering procedure must be performed. (Refer to 8 -
ELECTRICAL/RESTRAINTS/CLOCKSPRING - STANDARD PROCEDURE - CLOCKSPRING CENTERING).
PM
RESTRAINTS - SERVICE INFORMATION
8O - 361