When Weight Is Added/Removed

WEIGHT ADDED
When weight is added to the vehicle the air suspension system responds as follows:
- The air suspension height sensor length is reduced from trim length, sending a "rear is low" signal to the control module.
- The control module then turns the compressor ON by grounding the compressor relay. This restores the rear of the vehicle to trim position.
- The control module opens the spring solenoid valves. This allows pressurized air to enter the rear springs.
- Compressed air flows from the compressor through the compressor air drier air lines and spring solenoid valves into the rear springs.
- As the rear springs raise the rear body height, the air suspension height sensor increases in length until the preset trim height is reached.
- The control module then turns off the air compressor (through the relay) and closes the air spring solenoid valves.


WEIGHT REMOVED
When weight is removed:
- The air suspension height sensor length is increased from the trim length, sending a "rear is high" signal to the control module.
- The control module then opens the vent solenoid valve (located in the air compressor and opens the solenoid valves. This restores the rear of the vehicle to trim position.
- Compressed air flows from rear springs, through the air spring solenoid valves, air lines, compressor air drier, and out the vent solenoid valve.
- As the body lowers, the air suspension height sensor length decreases until the preset trim height is reached.
- The control module then closes the vent and solenoid valves.