Disco 2 Air Suspension Fault

Hi

Have had a search around on the forum and can't find this fault mentioned - might just be being blind though!

Noticed yesterday that rear air suspension was very low. Tried raising it and nothing happened. No noise from compressor.

Looked under bonnet and the Fuse was blown. Replaced the fuse today. Compressor started up and made the usual noise for adjusting the car but the back end still seems low.

Ride height light on the dashboard is on - and cannot manually raise the vehicle using the lift button on the dashboard.

Guessing its not the compressor as it sounds normal. Both sides are low so doubt its the air bags as surely only one at a time would go, plus that wouldnt explain the fuse? So assuming something electrical. Any ideas?

Its still driveable on-road at the moment as long as it doesnt drop any further - but planning to use it off road next Sunday so would really like to have my ground clearance back! Any ideas much appreciated!

I would say that your first job is to find out why that fuse blew, and just because it was changed until you've found out why it blew, there's no telling whether the replacement didn't blow too.
When you tried to raise the suspension with the dashboard switch, it would only work if all the doors were properly shut.
You've said that though the suspension has raised, it still seems a bit low to you. If the replacement fuse blew while the compressor was raising the suspension, it would stop at a point which could well appear to be low. This would indicate that the compressor motor though turning could be drawing too much current, indicating a possible faulty compressor. While a blown fuse is in circuit the manual raise button won't work either.
The Air Suspension (Ride Height) light will remain illuminated while a fault remains present on the SLS system. It is lit by the SLABS ECU.
So far as the bags are concerned, yes they tend to give out one at a time, but I (and many others) would recommend that both bags are replaced at the same time.
So to recap, I would say that at the moment the bags are OK and the ECU would seem to be doing what it should. Everything so far appears to point to the compressor being at fault.

The compressor can run but not pump enough air if the piston seal is worn in it .... to check that unplug all the connectors(the ones on valves have clips at the bottom) and improvise a wiring as to give direct battery feed(through a 30A fuse) to the compressor and air supply valves at the same time(scheme attached) , if it starts rising cut the feed before you overinflate the bags and we'll speak again if it will not rise this way you'll have to fix the compressor with this http://www.i6automotive.co.uk/wabco...it-old-generation-and-new-generation-covered/ and that can be the reason of the blown fuse too as the compressor worked too much without success and melted the fuse

Thanks

So... tried connecting as you said and nothing.

Removed the compressor pump unit from the rest of the assembly, tried just connecting that up and, again, nothing. Completely dead.

Decided as i'm almost certainly going to need to buy a new unit anyway to take it apart and have a look inside... the motor compartment smells strongly of burning and all the grease inside has gone black and hard. Couldnt turn the motor by hand at all. Cleaned off the burned grease and the motor now turns by hand but is very very stiff.

I am assuming my best bet involves buying a new compressor? On the plus side the air filter in the rear light cluster looks almost brand new

Compressors often come up on ebay (but of course rarely when you need one).

Having said that, this might be worth a punt: http://www.ebay.co.uk/itm/Discovery...2237141873?hash=item41b6a50371:i:282237141873

Or even this:

http://www.ebay.co.uk/itm/Land-Rove...9ffb393&pid=100005&rk=2&rkt=5&sd=282237141873

Replacement (second hand) Compressor bought from G-Tec in Melksham. Excellent service, phoned them at 8.45 this morning, nipped over and picked up the part, and had it in my hands by 10am. Home and fitted to the car and by 12 I had working air suspension again

£75 for the compressor - could have been a lot worse!

That's quite a good price - I think I paid about £150 for mine when I needed it.

I did then wait till one came up on ebay at a reasonable price and bought it for around £40 to keep in the garage as a spare.

iansoady said:

That's quite a good price - I think I paid about £150 for mine when I needed it.

I did then wait till one came up on ebay at a reasonable price and bought it for around £40 to keep in the garage as a spare.

Click to expand...

Good idea - might add it to my list of "things to keep an eye out for"

Obviously being second hand from a breakers yard i've no idea how much life this one has left in it.