Air Suspension Systems

A vehicle suspension air bag.

Airbags: In an air suspension system, airbags or air struts, replace coil springs and leaf springs. Airbag failure is typically caused by age and moisture within the system itself. The compressor uses a drier that can become saturated with moisture from the air. This moisture is then passed on to other components in the system. They also fail because the rubber dries out, especially at the base where the bag folds. Spray soapy water around the base when inspecting an airbag for leakage. Spray soapy water where the quick-connect o-ring connects to the line and watch for bubbles on the airbags and air lines.

Solenoids: The solenoids are located at each airbag or strut. They typically suffer from leaks at the connection where the quick-connect o-ring connects to the line. They can also leak where the solenoid connects to the airbag. These solenoids are electrical and can have an input or an electrical problem. Always follow the manufacturer's procedures and specifications when testing circuits.

Air lines: Air lines consist of nylon tubing approved for use in airbag systems by the Department of Transportation (DOT). These lines wear and can become damaged by scraping across sharp chassis and suspension parts. Use soapy water tracing a leak on route to the problem airbag.

Compressor: In time, the system's compressor wears, especially if there is a leak in the system. The compressor burns out, trying to keep air in the leaking system. Some of these have a failsafe. These newer factory systems are computer-controlled. Use a scanner to retrieve any codes that identify which part of the system to troubleshoot. The system connectors are often next to the computer in the trunk; disable the system with the switch located by the scan connector before raising the vehicle.