Load Leveling System
Air suspension load leveling system is a microprocessor-controlled active air suspension system. Air Suspension/EVO control module maintains a predetermined trim height. At speeds greater than 65 MPH, air suspension system lowers trim height for greater stability at high speeds. Air suspension system generally uses a 30-second interval between compressing and venting operations. No venting operations will take place while vehicle doors are open or during first 30 seconds after ignition switch is turned to RUN position.
Suspension height is monitored by 3 height sensors. Airflow within system is controlled by interaction between air compressor, solenoids, height sensors, door switches, speed sensor and control module. See Fig 1. Air suspension system is equipped with a self-diagnostic system. An air fill routine is preprogrammed into the control module memory.
When CHECK AIR RIDE message is displayed in message center, a system error or trouble code has been detected and stored by control module. Trouble codes can be retrieved using Rotunda New Generation Star tester. See appropriate MODULE COMMUNICATIONS NETWORK article in ACCESSORIES/SAFETY EQUIPMENT.