Suspension air compressor won't run W211 2005

[Oldspanners]

Having a problem as above. Just changed the rear height sensor as the rear was sitting a little low. Cleared faults with the iCarsoft but the pump doesn't run. Can access data of ride height by moving the sensor and command the pump to run without effect. The pump will run with a direct 12V feed. I can't find the position of the relay to see if that's the problem.
Any advice welcome especially a wiring diagram.

 

[Uncle Benz]

Underbonnet fuse box, driver’s side. Green one at the back iirc. 40A fuse in there too worth checking

 

[Wighty]

You changed cars buddy ?

 

[Oldspanners]

You changed cars buddy ?

If only Doing a bit of spannering for a friend who's MB has let him down slowly

 

[Oldspanners]

Underbonnet fuse box, driver’s side. Green one at the back iirc. 40A fuse in there too worth checking

Thanks have looked at a green one with 5 contacts and it checked out OK must try the fuse tomorrow.

 

[Uncle Benz]

Thanks have looked at a green one with 5 contacts and it checked out OK must try the fuse tomorrow.

Hmm, four pin relay for the compressor. You might have the wrong one

 

[Oldspanners]

Hmm, four pin relay for the compressor. You might have the wrong one

Yes that's what I assumed. Have had a look on youtube and it seems to be a black one at the very back of the fuse box in the engine bay drivers side. Relay S apparently.

 

[BigAlMercMan]

Hi, just replaced my compressor. Green 5 pin came out and was replaced by a 4 pin that came with the compressor. It is the one that is attached to the back of the box.

Thread

 

[Oldspanners]

Hi, just replaced my compressor. Green 5 pin came out and was replaced by a 4 pin that came with the compressor. It is the one that is attached to the back of the box.

Thread

Thanks for that looked at your post and the photo shows exactly what I'm looking for.
Did read your post when originally posted but couldn't remember where. Hope it's just the relay I'll get a look today.

 

[Oldspanners]

And finally. The pump wasn't putting out sufficient pressure due to the tube from the air filter falling off and allowing grit water etc in and ruining the piston and bore. The "new" rear level sensor was faulty and although sending info it wouldn't command the compressor to start. New compressor, relay and old level sensor faults cleared and everything back at the right height.