Column Adjustment 1 Vertical adjustment cam 2 Adjustment motor – tilt 3 Worm drive – tilt adjustment motor 4 Worm drive – reach adjustment motor 5 Adjustment motor – reach The steering column is adjusted using a four way switch located on the LH side of the steering column, below the LH column control switch. The steering column adjustment is achieved by two electric motors and a column adjustment control unit on vehicles without memory seats or by the memory seat ECU on vehicles with memory seats. Both motors are attached to the lock housing / tilt head assembly and move the column via worm drive screws. The reach adjustment motor drives a screw shaft which moves the column in and out for reach adjustment. The adjustment is achieved by the two extruded aluminium sections which slide on one another. The tilt adjustment motor also drives a screw shaft. This shaft is connected to a cam, which causes the tilt head to pivot, adjusting the column angle.
STEERING DESCRIPTION AND OPERATION 57-13 On vehicles without memory seats, inputs from the column adjustment switch are received by the adjustment control unit located under the column. The control unit interprets the signals from the switch and operates the requested adjustment motor in the required direction. On vehicles with memory seats, the adjustment control unit is not fitted. Inputs from the column adjustment switch are received by the memory seat ECU which is incorporated into the driver's seat switch pack. The ECU interprets the signals from the switch and operates the requested adjustment motor in the required direction. The motors used on the memory vehicles have Hall effect sensors known as 'ripple counters. These counters output the position of the column when the seat memory store function is used and applies this setting to the applicable ignition key.