Hi Can anybody help with my 03 XJ350 ( 3.6)
Out of the Blue AIR SUSPENSION FAIL came up on my dash, About a minute later the rear end raised and became rock hard, I stopped and re stared the motor which settled things for 10 mins or so but then it repeated itself. This happened more often until I got home. Diagnostics failed to pinpoint anything. Now off the road and looking for clues. All the mechanical parts seem to be ok. The car has not sunk displace being parked up for a week. The original Fail notice came immediately after the rear nearside wheel hit a fairly big pothole ( enough to make me swear.)

After 2 weeks the rear NS corner has sunk ( the side that hit the pothole )

 

Hi,

Are there no fault codes? I would have thought that Air Suspension Fault displaying on the dash would raise a fault code. If one corner is sinking it does sound like a fault in that suspension strut. Possibly leaking from the top.

Thanks,

Chris

 

Thanks
it did show a fault or two but nothing that related to suspension one was a CD player and the other a general code for multiple items.
I have just been out to it and the whole rear end has now sunk. Starting it made no difference. a slow drive neither raised it or bought up a fault on the dash.

 

Could you have damaged a height sensor when you hit the pothole? What is the height sensor position reading to the ASM when it goes high? If the ASM thinks the rear needs raised to get to “0” it would explain your symptoms.

Best Regards, William

 

First thing I would do after listening for hissing air is grab a flashlight and check under the car. The ride height sensors are mounted to the lower arms and are visible from underneath. They are clipped on and could be jostled loose. Check connector, wires leading away from sensor, and the little ball joint/armature that make up the moving part of the sensor.

 

Agreed with William and Victor, next thing after the air loss test is that if the car isn't throwing a fault then the car most likely thinks that corner is at the 'correct' height and therefore does not fill it with air. So the ride height sensor is mostly at fault possibly due to the pothole. It may have come loose or it's damaged.

Good luck.

Cheers,

Chris

 

Hi hiaryjohn,

Most air suspension-related DTCs are proprietary Jaguar codes, related to the Chassis (C-prefix), Body (B-) or Network (U-). These codes cannot be read by generic OBDII scan tools that can only read Powertrain (P-) DTCs.

If the good suggestions you've received so far don't help you resolve the issue, try to find a local shop with either a Jaguar IDS/WDS/SDD system or a high-end third party tool like an Autel MaxiSys, AutoEnginuity with the Jaguar enhancement, etc. iCarsoft claims their affordable i930 Jaguar Land Rover edition scanner can read Jaguar suspension DTCs, but I have no personal experience with that tool. However you obtain them, knowing the codes may help expedite the diagnosis.

Cheers,

Don

 

My iCarsoft unit does read all the Jaguar-specific codes. Its an i930 and I have used it to find out which wheel sensor was duff.

 

Just went through this with my XJ. It was a bad height sensor. I used IDS/SDD to check the reading from the sensors and the left rear thought it was high when it was low. Then when I jacked up the low side, the sensor didn't change its reading. New sensor in and all is well. If you don't hear/see any air leaking, probably a bad sensor.