Circuit Description
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 Chevrolet Tahoe, 2003 Chevrolet Suburban, and 2003 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
The vehicle's rear leveling compressor motor is switched on and off via a compressor motor relay which is controlled by the suspension control module. The suspension control module provides a switched path to ground whenever compressor activity is required. The suspension control module continually monitors the compressor motor relay circuitry to determine if the voltage level agrees with the commanded state.