Air Suspension Description

The air suspension module controls the inlet valves, the air suspension relay and both compressor assemblies to keep the rear suspension of the vehicle at the correct design height under loaded and unloaded conditions. The air suspension module will determine if the vehicle needs to be raised or lowered depending on the detected height changes determined by the left and right rear air suspension sensors. When the vehicle is raised, the inlet valves are opened and the relay is activated to start the compressor assemblies in order to inflate the rear air springs. Before both compressors are activated, the exhaust valve is opened momentarily to release air from a central chamber located within the valve assembly. Once both compressors are activated, the chamber is charged to a designed air pressure before the inlet valves are opened, which prevents lowering of the rear suspension caused by air exhausting from the rear air springs into the central chamber. As the rear suspension approaches the design height, both compressors will remain activated but only one inlet valve is open at any given time depending upon which side of the vehicle is not at the correct design ride height. Each inlet valve is switched closed and the compressor assemblies are switched OFF as soon as the design ride height is achieved on both sides of the vehicle.

When the vehicle is lowered, the inlet valves and the exhaust valve are opened so that air is exhausted from the rear air springs. As the rear suspension approaches the design height, the inlet valves are pulsed ON and OFF while the exhaust valve remains open until the rear height of the vehicle meets the designed ride height.