Compressor Amk Mercedes Class R W251

WARNING: the compressor does not break down on its own.

It is therefore extremely important to understand the causes of its malfunction before replacing it with a new/reconditioned unit to avoid another failure.

The general causes are:

The relay is not replaced and the compressor continues to run until it seizes; always replace the relay.

Even the smallest hole in the air spring, in the height adjustment valves, or in the system will cause the system to lose pressure and the compressor to activate more than necessary to bring it back up to pressure; the larger the hole, the faster the system will discharge. Therefore, carefully check that there are no leaks of any kind.

The compressor draws ambient air through an intake hose which is most often fitted with a filter. If this hose or this filter are damaged, the compressor could draw in debris, dust and water, resulting in internal damage and corrosion of the piston and cylinder. Therefore check that the hose and filter are intact and dry inside.