Hi,

I've got this common issue, from research it seems that it could be the air suspension compressor. But, before I buy this part and have it fitted I wondered if anyone can confirm it is that part.

When I start the car the compressor makes a bit of a noise until the dashboard light comes on and cuts it out.

I have had the fault codes read and there's a number of faults which all seem related:

C1A20 Pressure increases too slow when filling reservoir

U1A13 Lost communication with terrain control module

C1A02 Rotary encoder stuck in intermediate position

U0421 Invalid data received from ride level control module

Could anyone advise me on a next step - does this sound like the air suspension compressor?

Thanks for any help in advance

mine was the same , got a full rebuild kit off ebay , fitted and now good as gold , pump can be a problem to remove as they get very corroded

Mine was doing this each day, but showing no other symptoms, the garage confirmed a compressor was needed.

It was fitted a few months ago and good as gold for a bit, but it still comes up now and again. It seems to be one of those faults that throws up with any one of a number of issues. I know from reading here that other electrical gremlins that plague these cars can cause this too.

Next time mine is in for a service, they will plug it in and I am sure it will swallow another grand to turn all the intermittent lights out. Nature of the beast.