The electronically controlled air suspension, if equipped, keeps the rear of your vehicle level as you load and unload it. The system includes a compressor, two height sensor and two air springs supporting the vehicle.
The engine must be running for the system to level the vehicle after loading or unloading. The system will suspend transitioning between the designed ride height and the extended ride height if any of the doors are open. However, the system will not suspend operation during normal leveling and once the doors are closed, system leveling will continue.
You may hear the compressor running when you load your vehicle, and periodically as the system adjusts the vehicle to the standard ride height. You may also hear the release of air similar to a hissing sound during suspension operation. This is normal.
Load leveling will not function normally with the inflator hose attached to the inflator outlet. Remove the inflater hose from the outlet when it is not in use. See Accessory Inflator .
Overload and Overheat Protection
Overload protection is designed to protect the air suspension system and is an indication to the driver that the vehicle is overloaded.
If the rear suspension remains at a low height, the rear axle load has exceeded GAWR (Gross Axle Weight Rating). When the overload protection mode is activated, the compressor operates for about 30 seconds to one minute without raising the vehicle depending on the amount of overload. This will continue each time the ignition is turned on until the rear axle load is reduced below GAWR.
If the total rear GAWR (Gross Axle Weight Rating) is reached, the suspension may be slightly less than level. This is normal and does not mean there is a problem with the air suspension.
If the system overheats due to normal operation, the SERVICE AIR SUSPENSION message will not be displayed on the DIC, but the system will shut down and stop all leveling functions until it cools down. If the system overheats and sets the SERVICE AIR SUSPENSION message in the DIC, then there is a fault. See DIC Warnings and Messages for more information.
