System Operation

The air system suspension switch, mounted in left side of trunk, is used to control system operation during system diagnosis or repairs. The air suspension control module maintains vehicle at a preset height and provides a soft ride for normal driving, which is switched to a firm ride during hard brake applications, acceleration or cornering.

Air suspension control module receives inputs from height sensors (one on rear and two on the front) and controls air springs to maintain vehicle height. Additional control components are air spring solenoid, compressor motor and vent solenoid, and air compressor relay.

To raise vehicle, air suspension control module first turns on air compressor through the air compressor relay. After a one second delay, desired air spring solenoid is activated. Air compressor and air spring solenoid will remain on until air suspension control module determines vehicle has obtained correct height through input signals from height sensors. Air suspension control module will then turn off air spring solenoid and air compressor.

To lower vehicle, air suspension control module turns on vent solenoid on air compressor. Vehicle will lower until correct height is obtained through input signals from height sensor. Air suspension control module will then turn off vent solenoid.

Air suspension system will operate for up to one hour after ignition switch is turned off. During this interval, vent solenoid will operate as often as required. Air compressor, however, will operate only once.

Air suspension system will operate automatically when ignition is turned on. This provides battery voltage through fuse No. 5 to air suspension control module. Fuse No. 5 is located in fuse block below left side of instrument panel. Air suspension control module is located on left side of trunk, behind strut tower.

Under normal driving conditions, air suspension control module energizes the soft strut relay, which applies voltage to dampening actuator. Dampening actuator will rotate to the soft ride position.

Air suspension control module receives inputs from steering sensor, EEC-IV module, brake pressure switch and dampening actuator. Air suspension control module uses inputs to determine when struts should be adjusted for firm ride.

During hard turns, wide open throttle or heavy braking, air suspension control module de-energizes soft strut relay and energizes hard strut relay. Voltage is applied to dampening actuators. Dampening actuators rotate to the firm setting. When air suspension control module senses vehicle has returned to normal driving, hard strut relay is de-energized and soft strut relay is energized. Dampening actuators rotate to the soft setting.

If air suspension switch is off, with ignition switch on or if a system failure exists, the RIDE CONTROL light on message center will come on. The message center is located on instrument panel, to right of steering column.