This Preliminary Information communication provides information to the technician about vehicles that have a Service Suspension System message on the Driver Information Center and the rear suspension ride height is incorrect. Technician will find Diagnostic Trouble Code C0696 or C0711 set in Electronic Suspension Control. Technician will need to inspect air compressor assembly for wire damage and repair any damage do not replace the complete air compressor assembly. Some vehicles may have a Service Suspension System message on the Driver Information Center and may also comment that the rear suspension ride height may be low under a heavy payload. Technician will follow published Service Information diagnostics and if determine if the sensor needs to be replaced technician will need to replace a complete air filter, dryer, and sensor assembly. Some vehicles may have a loose hose hanging down in the left rear of the vehicle. Technician will replace the auto leveling compressor air inlet filter and hose assembly. Also some vehicles may have automatic level control compressor is no longer performing a self-test at start up. Be advised the automatic level system normally will not or very infrequently cycle the compressor at key up.