Symptoms of a defective compressor
One of the most common symptoms of a defective air suspension compressor is the low vehicle ride height of the entire axle. This is may caused in a faulty compressor, because it cannot inflate the spring bellows sufficiently. If the compressor does not start at all, there also can be a problem with the relay or fuse. These two components should be checked before replacing the compressor.
A defective relay can even mean that the compressor has to be replaced.
If the relay is stuck, this is called a "sticky relay". As a result, the compressor runs permanently and then overheats and loses its function quickly.
We therefore always recommend changing the relay when replacing the compressor.
Even if there are strange noises while running, you must assume that the air spring compressor is defective. A loud clicking, whimpering and/or grinding sounds are signs of a compressor that should be replaced.
In the rarest of cases, the air suspension control unit is the actual cause of malfunctions or error messages. This can often only be checked by specialist workshops.