I have a 2005 XJ8 L with about 52,000 miles. I have been getting the air suspension fault message for some time although it is intermittent. Sometimes a couple of months go by with no message. Recently it has come on more often. I have never received the ride too low message. I know I need to get it scanned. The problem is the Jaguar dealer is about 4 hours from me. There is no one local who has the equipment to do the scan. My dilemma is wondering if the car is safe to drive to the dealer to have it scanned and then driving it back home. I have already decided that if the compressor or shocks are the problem, I will convert the air suspension with the coil kit. From what I have read, it is not a case of if the air suspension fails, only when. Would I just be better off to do the conversion and skip the trip to the dealer. Wouldn't doing the conversion solve any air suspension fault problems. I am female and in no way mechanically inclined so anything I have learned about this problem has been read on forums. Any advice is appreciated.

 

Dear olypen123,

Welcome to the forum! I'm sorry to hear that you're having problems with your air suspension. As you've probably realized from viewing threads in this forum, air suspension faults are very common on the Jaguar X350. We still don't have all the answers, but collectively we are learning a lot.

It would definitely help to have the fault codes scanned, but it is hard on the air spring bladders to drive the car with the suspension too low, so I would advise against driving to the dealer.

My first question is, is the ride height of your car low, or does it seem correct? Are the tops of the fender arches sitting nearly on the tops of the tires, or are there a couple of inches of clearance?

One common possibility is that the piston ring in the compressor is worn and is not charging your system sufficiently within the 120 seconds allowed by the Air Suspension Control Module before it shuts off the compressor to protect it from overheating. But in my experience with our '04, we have always had the Vehicle Too Low warning before the Air Suspension Fault warning appeared.

You can test your compressor by starting the engine and listening for the air compressor to start running. It is mounted in front of the left front wheel, inside the front bumper. It is mounted with rubber and spring isolation mounts to help reduce noise, so with the engine running, you have to listen carefully for the air compressor.

The compressor should run for about two minutes, then shut off. If you still have the ASF warning, shut off the engine for 1 minute to allow the compressor to cool, then restart the engine and listen for the compressor to run again. When the compressor shuts off, if you still have the ASF warning, shut off the engine again for 1 minute, then restart the engine again and allow the air compressor to run until it stops. Hopefully, within about six repetitions of this procedure, the compressor will have charged the suspension sufficiently and the ride height of the vehicle will be correct. I can't remember off the top of my head if the ASF warning will go out without driving the car, so you may need to drive it around and exceed 25 mph before the warning is extinguished.

If restarting the engine several times recharges the air suspension and extinguishes the ASF warning, then your compressor probably needs a new piston ring. The part is inexpensive from forum member bagpipingandy, and a local shop should be able to replace it in an hour or less. I can supply photos of the process.

There are many other possible causes of the ASF warning, but please try the test above and let us know if it seems to help.

To answer your question about the coil suspension conversion, yes, if correctly installed, the conversion would eliminate the air suspension components and any future air suspension faults.

Cheers,

Don

 

Thanks so much for your help! I have been checking the height of tires to the body of the car for the past couple of days. There is at least a 2" clearance on all four tires. I have tried to determine if I hear the compressor. Either the compresser isn't running or I am unable to distinguish it. Ugh! The Air suspension fault never appears right after starting the car. It most times comes on after driving for a few minutes or even after an hour. Some days it doesn't come on at all. As I stated before, I have never received the vehicle too low message. I will try starting the car a few more times this morning to determine if I can hear it. I think I may be stuck with converting which may or may not be a good thing.

 

or maybe I should have my local mechanic replace the piston ring and see if that solves the problem?

 

If the car is not sagging, I have to assume the compressor must be working to some degree?

 

I too have a 2005 XJ8L. At 97,000 miles I started seeing the ASF message. Over the past year and a half, I've had a new air suspension compressor installed and replaced the left and right front struts (leaks). After the aforementioned repairs, the car rides fine, yet the ASF warning message still comes on intermittently. On more than one occasion I've left the car with the dealership multiple days and "no drop" discerned. I'm now at 99,993 miles (I've had the auto since 23,000 miles (early lease turn in)). I'm just about ready to give up and live with it unless the ride is impacted! Any ideas?

 

Oh, wow! Not good news for me. I am going to have my local mechanic replace the piston ring and see if that corrects the problem. If not, based on what you are saying, I will just convert to the coil/spring system for peace of mind. I have also had this car since about 25,000 miles and the air suspension fault has come on intermittently for at least the last 3 years ......sometimes it goes months before reappearing. I don't notice anything different when driving but I am no expert. It has never been sitting on the tires in any event. Seems like for as much as these cars originally cost, nothing should be going wrong at the 30-50,000 mile range. Mine was also a lease return. I am retired and only put about 5,000 miles per year on it.

 

Sounds stupid I know but ... get your battery checked. If the battery voltage is even a wee bit on the low side it can start to throw odd alarms (even 'though it's got enough 'oomph' to start the engine).

Does the fault appear when the car's been stopped for longer than usual ?

 

Since you've replaced the shocks, it seems the piston ring in air compressor is most likely the culprit.

 

Yes, I will have the battery checked out. Thanks! I can find no rhyme or reason for when the fault appears. I read somewhere else that water can condense in or around the compressor and if you drive it and bring it home and park it for awhile, then go out and start the car and rev the engine a few times, it will clear out the condensation. I tried this a couple of years ago and the fault did not reappear for quite some time. Don't know if it was just coincidence or not. It isn't correcting the problem lately. Supposedly this helps in humid, moist climates. It is summer now though and the fault is appearing although I believe in my case this is the first summer I have been having the problem.

 

I too will have the battery checked since my regular Service Advisor at the dealership did express some concern about the battery a couple of maintenance service visits ago (same battery since I acquired the vehicle some years ago). In driving the car today, the ASF warning msg never came on.

 

As for the piston ring in the compressor, it is a brand new air compressor installed in January/February 2014 (see my original posting on this subject). Thanks for the input.

 

Hi olypen123,

At least one member has reported finding water in his compressor. I found some rust that indicated enough moisture in the air in the compressor to cause some corrosion, but in general the air dryer should sufficiently reduce the moisture content of the air in your air suspension, so I personally doubt that water in the compressor is the cause of your ASF. And since the compressor has its own electric motor, revving the engine of your car will have no effect on "clearing" the compressor, and is generally not healthy for your engine either.

If I understand what you have reported, your car is not riding low, you have about 2 inches of clearance between the fender arches and the tops of the tires, and you have never had the VEHICLE TOO LOW message.

Can you tell us if, when the ASF warning appears, you notice any difference in the ride height or the ride quality of the car? Does the car sag low or rise up? Does the ride become either very firm or very loose?

If your ride height seems to remain consistent with about 2 inches of clearance at all four wheels, then I don't think you need to rush to replace the piston ring in the compressor, since it must be supplying sufficient air pressure to keep your car at the proper ride height.

I'm personally suspecting an electrical fault, and having the codes read would be the best step to take next before you spend a lot of money on service that may not resolve the issue. I will try to do some research in the manuals to see what can trigger the ASF while the suspension otherwise seems to be operating correctly.

Cheers,

Don

 

There is at least 2" of clearance from the top of the tires and the fender arches. The car does not and never has sagged. I have never received the CAR TOO LOW message. I do not notice any difference in ride quality when the fault is displayed. The fault seems to appear at random. Yesterday I ran one short errand (probably 2 miles) the fault did not come on. A couple of days ago I drove the car about 4 miles, and the fault came on at about 3 miles. A couple of weeks ago I drove about 160 miles and the fault came on about half way through the trip. It does not come on every time I drive the car but lately is more frequent. I have noticed a few times when starting the car in the morning that the car rises, but it has not done that for awhile. I did have an appointment in Seattle to have the car scanned and codes read at the dealer. I live almost 4 hours from there. I cancelled the appointment after reading cautions related to driving with the fault. My local shop cannot scan the car--his software doesn't support it. Called an import auto shop about 60 miles away, who advertises he works on Jaguars, and he said there was a 50/50 chance he would be able to scan for codes... huh?? Just called another local shop today, and his head mechanic says their scanner will "spit out the codes." I will take it Monday and see. I did check the battery cells and they look a little low on water so will also have them check the battery, I have no idea if the battery is the original one that came in the car but I suspect it is. That would make the battery nine years old. Some members are reporting even a slightly inferior battery will cause fault messages. But if that were the case, would it always be the same fault message? Awhile back I remember my GPS coming on out of the blue, but that hasn't happened again. I will report back what I find. Thanks for all the help!

 

Check the battery manufacture date (I believe on the negative post on the battery if it's a Jaguar original - you will see 2 numbers - like 08-04 (meaning 8th week of 2004) if your cells were low or your battery is more than 5 years old. (More than likely if it's original) I would plan on replacing it (in general) +1 to your compressor piston seal or you may have air leaks at the struts themselves (1 or more) or at the air line connection (again 1 or more)

Hope this info helps.

 

Does the fault appear when the car's been stopped for longer than usual ?


I also wanted to add (not sure if it makes a difference) that the ASF has never appeared when I initially start the car after sitting. It always comes on later--after driving for at least a short distance. If I stop and park the car overnight, the fault is never there in the morning. It does come back on when it has not sat for awhile, i.e., if I am driving for at least a few miles and the fault appears, then I park the car and it sits for an hour or so, then when I start the car, the fault is still there. But the next morning, the fault is never there.

 

Took the car today to the shop and they were able to perform the scan. The only code that came up was a battery code. I am going to have a new battery installed as I am sure the battery in the car is original. We will see what happens. Thanks again for all the help!

 

Please let us know how it goes, olypen123!

Thanks,

Don

 

Had a new battery installed today. After driving about 5 miles the ASF message appeared. Took the car back to the mechanic and he scanned it again. This time C2303 showed up. I was told to park the car on a level surface and take some measurements. Then in the morning I am suppose to go out and remeasure to see if the car has dropped, I guess. Not sure what is next, but I am leaning strongly towards a conversion.

 

Don't overthink it. C2303 means reservoir plausibility error and in most cases means the compressor doesn't pressurizes the system within the required time frame. That's why you get the message sometimes and sometimes not when there's enough pressure left in the system. In most cases it's the compressor that needs a new seal and it can be fixed with a $50 kit from Bagpipeandy (Google him or search on the forum). You mechanic can install within an hour.

Since your car doesn't sag there no reason to convert the suspension whatsoever. If any shocks need replacing it's early enough to think about that.

Guus