Principles of Operation

PRINCIPLES OF OPERATION

The air suspension module uses the standard corporate protocol (SCP) communication network to provide diagnostic information through the data link connector (DLC). The air suspension module monitors the inputs and controls the outputs of the air suspension system and also operates the variable assist power steering (VAPS) actuator.

The air suspension module provides the instrument cluster with a ground circuit in order to illuminate the air suspension warning indicator in the instrument cluster and also receives door ajar information from the driver door module (DDM). The door ajar information is necessary for the air suspension module to determine the vehicle may need a trim height adjustment.

The air suspension module also controls the VAPS actuator on the power steering gear which increases or decreases the power steering assist depending on the speed of the vehicle. The module receives the vehicle speed on a dedicated vehicle speed circuit hardwired from the powertrain control module (PCM) to the air suspension module.