Steering Wheel and Column Description and Operation
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Steering Wheel and Column Description and Operation
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The steering wheel and column has 4 primary functions:
The steering wheel is the first link between the driver and the vehicle. The steering wheel is fastened to a steering shaft within the column. At the lower end of the column, the intermediate shaft connects the column to the steering gear.
The steering column can be adjusted vertically and longitudinally
Theft deterrent components are mounted and designed into the steering column. The following components allow the column to be locked in order to minimize theft:
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The steering column lock
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The theft deterrent immobilizer module, if equipped
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Electronic Steering Column Lock
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Lock:
In order to lock the steering column, the ignition must be in the OFF position. Vehicles with automatic transmission: the gear selector lever must be in the P position to be able to turn OFF the ignition. The Body Control Module (BCM) will then check that the vehicle is stationary and one of the front doors is open. Once these conditions have been met, BCM will send signal to the Steering Column Lock (SCL) to lock.
Unlock:
When the ignition button is pressed, the steering column lock (SCL) unlocks if the transponder is approved. If the car has been parked so that the steering column is straining hard on the lock bolt, it may be that the SCL is unable to unlock. The SCL will then send a message on the bus and the Instrument Cluster will instruct the driver via its display to turn the steering wheel and try again.
The steering wheel and column may also have driver controls attached for convenience and comfort. The following controls may be mounted on the steering wheel or column.
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The headlamp dimmer switch
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The wiper/washer switch
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The redundant radio/entertainment system controls
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The telephone system controls
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The cruise control functions
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The automatic transmission manual setting function
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The steering wheel and column has safety features to protect the driver. The following components may be mounted on or near the steering column:
Energy-Absorbing Steering Column:
The energy-absorbing steering column compresses in the event of a front-end collision, which reduces the risk of injury to the driver. The energy-absorbing feature, collapsible steering shaft, and break away mounting features help reduce the injury in the event of an accident.
SIR Coil and Module:
For additional information on the operation of the SIR coil and module, refer to
SIR System Description and Operation
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Steering Wheel Angle Sensor
The steering wheel angle sensor is located somewhere along the steering knuckle assembly. The sensor measures the position of the steering wheel and the speed at which it is rotated. A signal representing this measurement is provided to the vehicle stability enhancement system (VSES) in the ABS module and to the variable effort steering (VES) system.
The theft deterrent immobiliser module:
The immobiliser module is mounted in the steering column lock on cars without Passive Entry Passive Start system (PEPS). Refer to
Content Theft Deterrent (CTD) Description and Operation
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