2008 TDV8 Air Suspension

Bought a air compressor pump repair kit off ebay, to service the compressor and the air dryer, which I did and all went fine. I removed the pump complete and serviced it on the bench. When replacing back in the car I noticed that the rear suspension had gone down, suppose tank is drained.
Re-assembled the compressor back into the car and now the rear the compressor runs for about 15 secs and then cuts out with SUSPENSION FAULT comes up on dash. It will not re-inflate the rear, the front seems ok.
Any ideas please guys?

Is compressor actually making air since you've rebuilt it?

Yes, gut for some reason it switches off after about 15 secs running, I have taken the compressor outlet pipe off and checked to see she is pumping and yes air is being pumped out.
Why has only the rear suspension gone down?.

Diagnostics is your friend....

Don't know the system so may be talking out of my *rse, (again) but did you put the pipes back in the right places.

Yes, they are clipped in line so it is obvious if you swap one over, I just don't know what keeps turning the compressor off.
Thanks for your ideas, much appreciated.

Faulty thermal cut out? Can it be overridden with diagnostics? I've ordered a new bale of straw, I'm running low on the grasping stuff.

The pump shuts off because the system is in fault, diagnostics may tell you more.....

BLOODY HELL
FOUND IT.
My fault, but even so I thought I would post my error as it may be helpful for someone else.
When I replaced the compressor piston components, (kit off of Ebay), when removing the cylinder head from the piston barrel, there is a very thin metal gasket with a hole in it. This fell on the floor when I opened it and when I reassembled it, I put the gasket back in the wrong way around...
Changed it around to the correct orientation (the hole nearest the compressor), and BINGO.
PERFECT.
As for the repair, what a difference, before the suspension was a DO NOT TOUCH, as it took ages to lift, now it is instant nearly, up, down, up again, very pleased.
Thanks for your assistance guys.