Hi,
I'm at a little loss. I have my OBD scanner left at my cottage and won't get it back for a few weeks. My car is giving the dreaded air suspension fault message and amber warning light. To me it appeared as though my compressor may have been running longer than normal so I went ahead and changed the compressors piston ring. Compressor appeared to be in fine shape and is running again, but I'm still getting the fault and warning message. Car appears fine although a little higher on right side than left? - it may have been like this before and not enough to b noticed without measuring. Car does not settle after a few hours shutdown. I have noticed that I can hear air flow or a leak in the vicinity of the left rear wheel. I can only hear this while the conversation compressor is running? Is that normal?
I have not yet sprayed all the strut fittings with soapy water because it has been too cold (below freezing) to do so. Anything else I should do or check before in hopes of finding fault before I get my scanner back?

Also, will the fault light and warning reset once issue is corrected or is a scanner or battery disconnect necessary to reset the fault?

Thx,
2005 VDP XJ

 

I measured height at each wheel and disconnected battery for the night. I disconnected battery so that car wouldn't self level, thinking that if a strut is leaking I should b able to tell which one in the morning?

 

The air suspension stops functioning once the fault appears, until the car is shut off and restarted. That's all that is needed to reset, just shut the car off.

You will NOT get any useful troubleshooting with guesswork; you've GOT to get that scanner and read the DTCs. 99% shot that the error is C2303, reservoir plausibility since you said the compressor runs long. That means that the pressure tank does not come up to pressure as expected, and the control module shuts the compressor off and gives up. The error doesn't point to any specific cause, it merely states that for some reason the tank won't come up to the desired pressure. That implies a leak somewhere.

My speech every time this happens to someone is give it up and go to coilovers. It's not sacrilege, and you're NOT giving anything up in ride quality. My car became useless a few months after I got it, I gave up and installed Arnott coilovers, and it transformed the car. The only thing you're giving up is having to park the car because it won't come off the bump stops. Personally, were I shopping for one of these at the moment, I would not be remotely interested in one that was still riding on the air system.

The remaining value of the car does not justify the expense of maintaining a 20-year-old system that is at twice its design lifetime. For less than a couple of grand you can be done with suspension problems, Forever.

 

So, after all night and most of the day with battery disconnected my car only settled about 1/8-inch on 3 corners and stayed the same on passenger (right) rear. Just trying what I can until I get my scanner back.

 

Well I would say nothing to worry about. That could be as much as O rings not sealing properly on those brass fittngs where the nylon hoses go in...
at least that is nothing the reservoir when full can't handle over 2-3 weeks. ( 5 liter 10-12 bar) airsuspension struts min. 3 bar due to lower brass fitting retention valve and then up to approx 6 bar for normal height and properly working struts.