I have a 2010 XJ (x351), which I’ve had for around 4 years. It has been trouble free until a couple of days ago, when the words “Suspension Fault” suddenly appeared in amber and the warning has remained on since. So every time I start the car I get a bing sound and the warning appears. I have 2 different OBD2 devices and neither of them finds any faults!?

The car drives as good as it always did, so whatever the fault is it has not (so far) impacted the car.

Does anyone have any suggestions on what the likely cause is or how I can get more info about what the exact issue is, like a fault code?

Thanks in advance

 

Sendel, you probably need to have an SSD computer connected to read the body codes (B-codes, these are not read by most code readers). I had a similar problem and in my case, it turned out to be the right front shock was not indicating properly back to the computer. In my case, it would stiffen up the suspension (which should be happening to you too). I replaced the shock myself and got back on the road for not too much. I have heard of 2 cars having this same issue. Not saying that is the exact issue of your car, but the right front seems to have its quirks on this car from what I have seen.

 

Good advice from Thermo!
Yes the code readers you have can't see the deeper Jaguar only type codes.
.
.
.

 

@Sendel not to rush to any conclusions . . . but also check that your battery is good condition. I have experienced those exact symptons plus the rear air suspension would be under or over inflated (often unevenly).
Good luck, let us know how you get on.

 

So sorry to jack the thread, but I have been looking for a solution to 'over inflated' rear suspension and how to remedy this. Any chance you can point me in the right direction to look up remedy for this?

Thanks,
Dan

 

Hi Dan - for me, it was a battery replacement. The air suspension system is very sensitive to batteries with low power reserves and marginal
Terminal Voltage. I fully cycled my battery with high quality battery charger; suspension fault disappeared after a full drive cycle, only to return a month later. Battery replacement fixed the issue, it has been more than 12 months now, not a single issue. Please note that completing a drive cycle is very important. Even with a new battery fitted, the suspension system will not recalibrate until a full drive cycle is complete. I posted elsewhere on this forum about that. Good luck, let us know how you go.

 

Dan, I had the opposite problem where the rear would not fill up. But, you can probably solve it the same way. No matter what I did, it would not correct itself. I ended up using the SDD software and getting into the calibration procedure for the suspension. There were two settings, normal and fine (or something like that). You want to use the fine and just let the car press up the system and then back out of the program. Once I did that, all has worked fine for the last few years.

 

A good independent will be able to sort this for you. Instead of consulting Jaguar all day long on this, I decided to buy an Autel 906BT (now superceded by a newer model). I can calibrate the suspension, and do most things SDD can do without the hassle of setting it up. I can also service all makes and other models that my wife drives or neighbors, etc.

I would start with that. If you want to DIY, a number of tools out there in the aftermarket that can do what you need them to do.
The calibration specifications/settings are in the service repair manual in the stickies at the top of this forum.