For 1990-2009 cars

The solid-state height sensor detects height changes at the rear of the vehicle and, in turn, controls the functions of the compressor and exhaust solenoid. To prevent energizing the compressor relay or exhaust solenoid during normal ride motions, the sensor circuit provides a fixed delay before ground is completed to either circuit.

In addition, the sensor limits compressor run time and exhaust solenoid energized time to a range of 4.5 to 7.5 minutes. This prevents continuous compressor operation in case of a severe system leak or continuous exhaust solenoid operation. The timer circuit is reset whenever the ignition is cycled OFF and ON, or the sensor exhaust or compress output signal changes.

The sensor is mounted on the right side of the underbody. The sensor actuation arm is attached to the right rear control arm by a link.