Air Suspension Compressor Assembly - Operation
OPERATION
WARNING:
All pressurized air suspension components contain high pressure air (up to 220 psig). Use extreme caution when inspecting for leaks. Wear safety goggles and adequate protective clothing when inspecting or servicing the air suspension system. A sudden release of air under this amount of pressure can cause possible serious or fatal injury.
WARNING:
Support the vehicle by supplemental means before performing any work on the air suspension system to prevent the vehicle from changing height. Before any given component is to be serviced it must be deflated. Servicing the air suspension system without supplemental support, or with pressure in the specific component, can cause possible serious or fatal injury.
The air suspension compressor assembly is made up of two primary components, the compressor and the valve block. There is a single pressurized air line between the compressor and the valve block to maintain system pressure. Control of the air compressor and valve block is from the Air Suspension Control Module (ASCM). Diagnose the air suspension system using a scan tool.
Air Compressor The compressor runs to maintain air pressure any time the vehicle height is being changed or in the event of a small reduction in over all system pressure. Integrated reversing valves in the air compressor allow pressurized air to be moved in two directions, making this a closed system. There is a desiccant located inside the compressor for moisture protection, and an air suspension hose assembly attached to the air compressor with a discharge hose and an intake hose (including a filter) which are not pressurized, and can be replaced as an assembly. If water is visible in the filter, the air suspension hose assembly and the valve block must be replaced. An air suspension temperature sensor is attached to the air compressor bracket to monitor ambient air temperature for protection of the compressor.
Positive voltage is from a 40-amp fuse located in the PDC, and a normally open compressor relay (ASCM controlled) located in engine compartment area, and ground for the relay and compressor are through a bolted on eyelet connection.
Valve Block The valve block controls the flow of air in the system and to maintain the pressure in the in each air spring which allows the system to move each corner of the vehicle up or down as necessary. Valves and solenoids in the valve body increase or release pressure to air lines that connect to each pressurized component. The ASCM determines pressure from an internal pressure sensor in the valve body. The air lines connected to the valve block are labeled for individual replacement.