My 2006 LR3 recently began having the suspension air compressor come on and start to run a little long upon initial startup. Suddenly it is on non stop while driving no matter what height I am in.

The system can raise and lower to any height, albeit a little slow, but it will go from normal ride height to off-road or down to access height and the entire time the compressor is running non stop until I shut the vehicle off.

I was going to tackle the valve block o-rings in the front and rear as I figured they were worn.

A list of suspects:

• valve block o-rings
• valve blocks themselves
• Relay
• fuses
• Suspension storage tank
• compressor itself and any lines around it
• air struts and lines around them

Are there any suspects I have missed?

Thank you

 

I would guess the relay because the compressor should only operate for a specified period before it faults. And when lowering, for example, the compressor can NOT be running because the system has to dump air. If its running when lowering you would, in theory, just raise the vehicle up. Thus if it is running non-stop, you have some really weird weirdness going on. But start with the relay. You can steal pretty much any of them from the box for testing.

 

Thank you for taking the time to respond and help me with this.

I swapped relays for R7 and R9, and still the compressor stayed on. When it is lowered it stays off, but the moment it reaches its intended height it kicks in non stop.

Upon looking around I spotted a fuse with the icon for height adjustment…

I then pulled the 5A fuse for the compressor (fuse F3 in the engine bay) that gave me an error on the dash that the vehicle is stuck in normal ride height. The compressor went off. I replaced the fuse and fired up the vehicle, and the compressor kicked back on non stop.

I dug out my iCarSoft CR Max reader and pulled a bunch of faults.

There was one area that caught my eye…

RLM (Ride Level Control Module) and it had two faults. Please see attached picture.



Lost connection with module errors U0132-87 and CA100-88

Now, a while back I had replaced the drain tube in the drivers side footwell area and was mucking around in that area. I know that the module is under that area as well, albeit, raised and oddly positioned.

I may have accidentally loosened a connector / wire in the vicinity when working in there.

There was no hissing or leaks in the wheel wells with soapy water on the lines. I have yet to check the blocks and lines at the compressor.

I will investigate and report back.

 

The compressor has a 30 amp fuse I think. No way it's just 5 amp. You may have pulled the fuse for the air ride computer but in my truck that is 10amp.

Lost communication faults are nothing to worry about and mean little usually.

So its interesting it shut off with that small fuse though. That tend to imply the main wiring for the compressor is not shorting out and that the relay, as you tested, is fine too. Meaning that for some reason the air ride ECU is in fact commanding it to run. Or its shorting the relay causing it to run. Check those connectors as you plan.

 

You are correct sir!

fuse F3 is 5A for the Air Suspension ECU

fuse F26 is 20 A for the Air Suspension ECU

Will continue to investigate and thank you

 

70a relay for the compressor, was 60a but they uprated it to 70a. Its a generic relay that can be found at any good car parts or electrical store.

 

Thank you, and as per DakotaTraveller, I swapped relays within the box and no change in symptoms.

So onto checking the wiring as it appears not all the water was removed from the carpeting.

Will report back with major findings once I’ve whittled down the smaller things, unless it’s a small thing that makes a difference

 

Interesting follow up.

Had someone spray paint / vandalize my vehicle today. Was not a fun day.

Took it in to body shop after dealing with insurance.

Compressor was on on the way there the whole time. Coming back compressor stayed off.

Got home gave car a thorough wash and now waiting to get it booked in.

Upon washing it and cleaning the wheel wells and everything, it looked good except for the neon green… firing it up to park it outside and let it finish drying.

The air compressor came on and stayed on.

So this is leading me to suspect more and more an exterior wire or wires are shorting, frayed or a connector is also not working.

 

The vandalism is complete crap, sorry man. What is the body shop gonna do? Repaint? Can you get the spray paint off with a clay bar? May be worth a try….a lot cheaper.