Air Suspension Compressor

I noticed a couple of weeks ago that my air suspension was no longer rising on start up. It does not sink by much when not in use but obviously does lift a little initially. On pressing the button to raise the rear suspension, nothing happened. On getting underneath the compressor could not be heard running either. This compressor was fitted 18 months ago and I was a bit dissappointed that it seemed to have failed. My local LandRover garage confirmed it was mullared and probably due to water ingress via the inlet breather behind the rear light. So, I bit the bullet and bought a new compressor and fitted it whilst also checking the breather pipe for water which was totally clear. After fitment, I started her up and everything was fine. The vehicle was now level again, the suspension went up when the 'raise' button was pushed, and the ride felt better again. That was 2 weeks ago and now I am back to square one again. The compressor is not cutting in and the vehicle is not level when stationary. I am totally exasperated with this problem. Could a fault code in the ECU caused by the earlier compressor failure (if it was a failure) now cause the new compressor to be switched off. I love the air suspension on my disco as the ride is much more smoother that my previous coil sprung version but this is becoming an annoying PITA. Any clues to what the problem may be would be very welcome.

Check the most obvious things first: Fusible link FL9(30A) and relay R5 from engine bay... if both are good then u can take out the relay and with ignition on bridge with a piece of wire it's contact pins in the fusebox.... if the compressor wil start working then it means the relay doesnt get feed on it's coil from the ECU.....then the diagnose could become more difficult.... e.g. if a door/taildoor switch is faulty the ECU will consider it open and wont command the compressor... etc. Usually for system/ECU faults there is warning on dash.

Many thanks for that Sierrafery, I shall look into this tonight.

Hi All,

new poster, but been an avid reader for several years, been down both the air bag replacement and the compressor replacement road before and found excellent information here.

but now I have a new problem;-)

my compressor does not seem to be getting any power.

I have narrowed it down to severla option but I am unsure how to test these, maybe you lot c an suggest something.


1. Fuse blown : I have checked all that seem applicable.
2. Hight sensors broken: Dont really know whathe symptoms would be, but its sitting flat to ground, and compressor not running.
3. Door sensor broken, making it appear that the door is open so the compressor wont run, this is what I think/hope the problem is but I dont know how I could test this.

would love to hear other suggestions or how I can test the above.

is a disco 2 btw

Thanks

Redmond

ive got a 53 plate disco and i dont think my compressor is working as the ride is rough
my back door sometimes dosent want to open could it be just this
thanks for all your help

After spending a lot of time going through various electrical checks I decided it was time to change the compressor. I managed to buy a new one for £320 of my local Landrover Spares shops and it only takes minutes to fit. Bingo, everything is back to normal, the car feels great again and she riding level. 6 weeks down the road and I'm back to the same situation ??? done all the checks again but nothing seems to be obvious why it has stopped working. I start to think that perhaps my SLABS ECU has a fault but of course I cannot check that out as I do not have the equipment. I bite the bullet and book it into my local Landrover specialist, not the mainstealer though. He calls me to tell me that my compressor is fecked because it is full of water and that there is even water in my airbags. He cleans the system, changes the compressor and modifies the compressor air intake to prevent a re-occurance. It now feel fine again and I am £740 lighter for the experience plus of course the £320 for the previous unit.I do love these vehicles but its hard to justify this sort of expense regularly and it does seem to be regularly. I always say to myself, now I have spent the money the vehicle should be OK.......I wish.

The problem with just changing the compressor is that the water is often still in the inlet pipes, so you put a new one on and it sucks up all the crap.

The design of the air filter is poor - it is located behind the rear light cluster, just below the sunroof drain tube (smart!)

hello all, i have a 2002 LR discovery 2 with SLS.
i noticed recently that once i park the vehicle the back is lowered when the vehicle is on normal ride while it doesn't lower at all when i select off road before parking.
please what could be the problem.

if there is a leak, how can i possible trace the position and what do i do to fix the problem.
please note that the back lowers evenly when it drops and rises once the engine is running.

i'll appreciate your quick response.

most times when the engine is running, i hear a hissing sound. what could that be.

i raised the height to off road and it has not gone down in 5 days now. is it normal to go down on normal ride hight.

thanks for your quick response.

let it on normal height and spray the airsprings with soapy water.... they used to seal themselves on ORM cos the leaks are usually on the extemities. if u'll not see bubbles there, take off the compressor housing's cover and spray in there too...it might be the exhaust valve which closes on bigger pressure but relieves on normal level...though my money is on bag leakage.... find out the problem ASAP otherwise u will end up with a burnt compressor too...and if a bag is leaking replace both anyway

Hi all
And thanks for the info you have passed on so far,
I have a problem with the rear air bags not inflating I have check fuses and check pipes to the bags all ok
But with all the doors closed engine running I can not fell the compresser running.
Will or should the compresser run with the pipes disconnected ? Am I right in thinking the short pipe goes in the middle Union and the pipes to the bags go on the out sides Unions.