Diagnostic Aids

Various electrical and pneumatic fault conditions can prevent correct leveling system operation. Although some of the fault conditions will cause storage of corresponding Continuously Variable Road Sensing Suspension (CVRSS) fault codes, none of them will cause a "SERVICE RIDE CONTROL" message. If CVRSS codes are present, refer to ELECTRONICALLY CONTROLLED SUSPENSION.

If a complaint of incorrect vehicle leveling occurs, always begin the diagnostic procedure by performing the following:
1. Check Electronic Level Control (ELC) position sensors for disconnected or damaged links.
2. Perform the "ELC System Check."

The CVRSS/ELC system is designed to stay powered up for a maximum of 5 minutes after the vehicle's ignition has been turned off. This time is to allow the vehicle to perform exhaust functions after a load has been removed from the rear of the vehicle.

A weak battery can cause the ELC air compressor to not run at full performance without storage of CVRSS codes.

If the vehicle has a harsh ride, always begin the diagnostic procedure by performing the ELC System Leak/ Performance Test.