GM Service Manual Online
For 1990-2009 cars only

Steering Wheel and Column Description and Operation RHD

The steering column is an energy absorbing type. It is designed to progressively compress under impact from either direction and contains a combination ignition/steering lock housing. The steering column is also equipped with a tilt/reach feature as an integral part of its design, which allows the column height/length to be adjusted to suit driver comfort. The ignition/steering lock is located on the right of the column assembly. The housing of the ignition/steering lock assembly forms an integral part of the steering column outer tube and cannot be replaced as an individual component. The steering lock is activated when the ignition switch is turned to the lock position and the key is removed. The lock engages into a slot in the steering shaft (when the slot is facing the lock mechanism) and locks the steering in position. The end of the ignition barrel assembly shaft is stepped and engages with the ignition switch attached at the back of the lock housing. The ignition switch is activated when the ignition lock cylinder is rotated. The steering column shaft is supported by the top and bottom bearings of the steering column outer tube. The steering column shaft connects the steering wheel to the steering gear, it consists of a solid shaft, a telescopic shaft, two universal joints and a vibration damper. For vehicles fitted with Electronic Stability Program (ESP), a steering angle sensor is attached to the inflatable restraint steering wheel module coil mounting bracket located at the top of the steering column assembly. The steering angle sensor is used to measure the position of the steering wheel. The telescopic shaft assembly consists of an upper tube that slides over a lower shaft allowing the shaft to transmit torque but still collapse in the event of an impact. The upper end of the steering column is attached to the instrument panel support structure by 4 bolts housed in breakaway mounting capsules at the steering column assembly mounting points. Should the vehicle be involved in a collision and sufficient force be exerted by the driver against the steering wheel and deployed inflatable restraint assembly, the mounting capsules will separate from the steering column allowing the steering column assembly to move down. Collapse load control is achieved primarily by the breaking away of the mounting capsules from the steering column assembly and the tension applied by the two control springs.