Flow of Diagnosis

WARNING: THE ELECTRICAL POWER TO THE AIR SUSPENSION SYSTEM MUST BE SHUT OFF PRIOR TO HOISTING, JACKING OR TOWING AN AIR SUSPENSION VEHICLE. THIS CAN BE ACCOMPLISHED BY TURNING OFF THE AIR SUSPENSION SWITCH LOCATED IN THE REAR JACK STORAGE AREA. FAILURE TO DO SO CAN RESULT IN UNEXPECTED INFLATION OR DEFLATION OF THE AIR SPRINGS, WHICH CAN RESULT IN SHIFTING OF THE VEHICLE DURING THESE OPERATIONS.

Check the operation of the parking brake system with the vehicle on a hoist and the parking brake control fully released. Check for any damaged cables and replace as necessary. Check the rear brake adjustment or perform brake system diagnosis.

Check the parking brake by depressing the parking brake control pedal. The parking brake must hold the vehicle on an incline by applying pressure to the pedal before it reaches full pedal travel to the floor. If not as specified, check the parking brake system for proper rear brake adjustment, cable operation and parking brake control operation.