Description

Steering Column

NOTE:
A = Hardwired connection.









STEERING WHEEL HEATER (WHERE FITTED)
The heated steering wheel module receives a power supply from the extended ignition relay in the EJB (engine junction box) via the clockspring. When the driver operates the heated steering wheel switch, a path is completed between the switch and the heated steering wheel module, which then supplies power to the heater mat. The heated steering wheel module monitors the heater mat temperature using the temperature sensor, and controls the power supply to keep the heater mat at the optimum temperature.

INTERMEDIATE SHAFT









The intermediate shaft consists of inner and outer steel tubes that can collapse telescopically to isolate the steering wheel from any movement of the steering gear during an impact. The tubes are bonded together with a stiff thin-walled elastomer to help isolate road noise. Universal couplings connect the ends of the intermediate shaft to the upper column and the input shaft of the steering gear.

UPPER COLUMN









The shaft of the upper column is installed in a bearing housing that is attached to an inner bracket with a pivot pin and an adjustment locking mechanism. Slots at the attachment points, in the bearing housing and the inner bracket, allow the bearing housing to move axially and to tilt in the inner bracket, to provide the rake and reach adjustment of the steering wheel. The locking mechanism is a friction lock, operated by a lever turning a cam disc.
The inner bracket is located on rails in an outer bracket, which is attached to the cross car beam. The inner and outer brackets are locked together by an energy management plate, which is attached to both brackets with screws. In a serious impact, to prevent excessive force causing injury as the driver strikes the air bag, the inner bracket progressively moves forwards on the rails in the outer bracket. The movement is controlled by the energy management plate. The plate has leaves attached to the inner bracket, which peel back in a controlled manner, absorbing energy and allowing the steering wheel to move with the driver.
The steering wheel module is attached to the top of the upper column by two bolts. The module incorporates the clockspring and the multifunction switches for the exterior lighting and the windows and washers.
Upper and lower shrouds cover that part of the upper column not concealed by the instrument panel. On vehicles with passive entry passive start, an IAU (immobilizer antenna unit) transceiver is installed in the lower shroud. For additional information, refer to Anti-Theft - Passive Anti-Theft - Passive

Electric Steering Column Lock (All Except NAS)
An electric steering column lock is attached to the underside of the bearing housing. On NAS (North American Specification) vehicles, only the body of the lock is installed, to provide a forward attachment point for the steering column lower shroud (as well as the internal mechanism being removed, the lock has also been disabled in the car configuration files). For additional information, refer to Anti-Theft - Passive Anti-Theft - Passive

Steering Column Collapse Actuator (NAS Only)
A steering column collapse actuator is installed to provide increased energy absorption to allow for a driver not wearing a safety belt. If the driver is wearing a safety belt and a crash situation occurs, the actuator is not activated.
The steering column collapse actuator is located below the energy management plate. A pin on the actuator is engaged in a hole in the central leaf of the energy management plate. When the driver safety belt is not fastened and a crash situation occurs which requires the driver air bag to be deployed, the RCM (restraints control module) activates the actuator, which retracts the pin from the central leaf in the energy management plate. This provides the required increase in energy absorption to allow for the additional loading caused by the unrestrained driver.

STEERING WHEEL









The steering wheel is located on the hexagonal drive end of the upper column shaft and secured with a M10 pan headed screw.
The driver air bag and two multifunction switchpacks are installed in the center of the steering wheel. On automatic transmission vehicles, upshift and downshift paddle switches are attached to the front of the steering wheel. A link harness connects the steering wheel components to the clockspring.

Steering Wheel Heater (Where Fitted)
The steering wheel heater consists of a heater mat and NTC (negative temperature coefficient) temperature sensor installed around the rim of the steering wheel under the trim. A heated steering wheel module, integrated into the link harness, regulates the temperature of the heater mat. A switch on the LH (left-hand) multifunction switchpack switches the heater on and off.
A heater symbol in the switch is illuminated amber when the steering wheel heater is on. When the steering wheel heater is off, the symbol is either not illuminated or, if the exterior lighting is on, illuminated green.