Circuit Description
WARNING: This page is about a different car, the 2007 Hummer H2. However, it is still accessible from the selected car via links, so may be relevant.
The air suspension module monitors the run time of the compressor. If the compressor has run for more than one hour during an ignition cycle the air suspension module switches OFF the compressor relay. The run timer counts down when the compressor is OFF with the ignition ON.