2004 XJ8 is to low but no air suspension fault. i only noticed its too low when i back up from my driveway the rear fender scratches the street surface.

i've searched the forum as much as i can but found nothing similar to my problem. i still can drive without screwing up the tire shroud.

 

forgot to mention car has 105200 miles on it and i only have it for 6 months.

 

It's possible the ride height sensor has gone bad, or the actuator arm has come off.
Not sure exactly where they are, but normally they would be between a suspension arm and a fixed point on the chassis, may be just 1 on th erear, or 1 on front and 1 on rear, but I'm sure someone else will let you know exactly where they are.
Anyway, It's just a little hinged lever, with a switch, and if the arm becomes detached the switch will "think" the car is at height, they can also be adjusted, I believe.

 

Here is a pic of the height measurement "lever" on the rear of my 2005 XJR.

You can see that it is anchored on the middle of the upper suspension support arm and extends down as a lever attachment at the bottom.

Rotate picture right 90 degrees. For some reason it uploaded rotated 90 degrees left!

 

On my car I have two height sensors on the rear and one on the front.

I broke the upper wrap around clamp on one of the rear ones when I was replacing all of my bushings. I used a tie clip to make the upper clamp fasten in place with no problems.

 

Thanks a million brian5 and jackra_1 for a mountain of info. I'll certainly check those sensors out. Being ultra new to the jaguar, i have yet to find these sensors... I'll let u know

 

What's happening is the ASM module thinks all is well with the suspension height so the fault points to one of the height sensors. I would get the car up on a ramp and get these all inspected for security and damage following which you may have to get a new height sensor or two, then get the ride height re-calibrated. This is an easy job with the relevant software on a laptop.

 

To Fraser Mitchell's point I used my JLR SDD software to re-calibrate my ride height after having the rear jacked up to get at the rear suspension.

After lowering the car the rear was about 2 inches too high.

Riding around a while may have resettled things however I chose to re-calibrate the ride height.

It is a lengthy time consuming process as you have to do each corner separately with very accurate measurements as to actual height.

The JLR SDD program I was using actually failed at the end however the ride height at each corner was spot on and still is.

 

just as Fraser Mitchell suggested, i finally got the jag up, all suspension height is firm and well. found rear passenger shock is soaked with oil - old leak.

i by passed the pump relay to turn on the air pump, found the air pump to be working 'ok' by its sound. no pressure gauge any where in the system. the car still is 4.5 inches off the ground and no air suspension fault.

 

this is the rear passenger side height sensor where the leaking shock is.



the other end of the height sensor.

 

The suspension struts consist of a hydraulic shock absorber and an air bladder all in one.

If you have evidence of oil on the strut, the shocker may have leaked, and that is why

you don't have an air suspension fail message or light.

 

hi meirion1, one shock absorber has leaked out no question about that. but how will that not send the air suspension fault though... new shock absorber on order.

 

Have you checked your fuses yet?

 

Yes Cherry_560sel, all fuses checked all good.

 

Hi tampuhaw,

Welcome to the Jaguar Forums! It's great to have you with us.

It does sound as though you definitely need a new air spring/shock assembly. I will be curious to hear if it resolves your ride height problem. Ordinarily it is the air spring, not the shock, that determines ride height.

For a summary of the air suspension components and their operation, see this post:

Air Suspension & ECATS System Summary: Components & Operation

This summary includes the factory specification for ride height, so you can determine exactly how low yours is running, and there are links to various factory documents that may be helpful.

In the meantime, please visit the New Member Area - Intro a MUST and post a required introduction so we can learn something about you and your Jag and give you a proper welcome.

Cheers,

Don

 

Halleluia...!!! i'm the only Jag nut ecstatic at reading the 'air suspension fault' this morning on my way to work. as soon as i got to work, i paused a few minutes before restarting 3 or 4 times... each time i can hear the air compressor cycling until it stops in middle of the last cycle just to light the air suspension fault immediately. the car is about 1 inch higher than it was yesterday and feels like smoothly gliding thumping over any bump and potholes i can find along the way.

as soon as i got home this afternoon though, still jubilant for the miracle... i kept starting and restarting to study and observe anything now that there is communication with the ASM, relay & air compressor. i now have 'car too low' fault.

all i can recall doing yesterday are as follows:
1. jack up the passenger side rear wheel exposing the leaky strut thereby stretching the rear wheel assembly.
2. thinking that the garage door controller was deemed inoperable after the last rain, i thought of pressing all its buttons many times hoping that it might have some connections to the ASM. this is of course one of my wild guesses.
3. bypassed the air compressor relay by replacing it with a 25amp fuse twice in an attempt to raise the car.

these are all i can remember that 'may' have something to do with my jubilation today.

Don B, my next stop is the New Member Area.

 

Hi tampuhaw,

It is very likely that, in addition to a leaky air spring, your system is compromised by a worn piston ring/seal in the air compressor. Many of us have experienced the issue of the air compressor struggling to repressurize the system. The solution is to replace the piston ring with an inexpensive kit manufactured by our member bagpipingandy (bagpipingandy.com). The links below show how I did it. Note that most owners don't bother to replace the desiccant beads in the air dryer as I did, but it is a good idea to open the air dryer, clean any rust or gunk from the leave valve and spring, and bake the desiccant beads in a 500F oven overnight to partially reactivate them. Sorry the large images are not currently working while Jag-Lovers reportedly is transitioning to a new server:

Air Compressor Rebuild Part 1 of 7
Air Compressor Rebuild Part 2 of 7
Air Compressor Rebuild Part 3 of 7
Air Compressor Rebuild Part 4 of 7
Air Compressor Rebuild Part 5 of 7
Air Compressor Rebuild Part 6 of 7
Air Compressor Rebuild Part 7 of 7

Cheers,


Don

 

bagpipingandy repair kit on order. i'm now thinking beyond the rebuilt air compressor. somehow i think the newly rebuild air compressor will still die off while cycling in 2 minute intervals just as it does today without finding what causes it to die in the first place.

i've listened to this air compressor cycling many many times that it always comes on (never failed to start) and also always dies off after a few cycle runs thereby lighting the air suspension fault (ASF).

 

I'm happy to report that it only took about 6 miles of driving after i replaced the leaky passenger side rear strut before the 'vehicle too low' light went away. no more 'air suspension fault' either. i hope for good because i haven't done anything yet on the air compressor. i'll drive for a week or two and see if the air compressor needs attention or not. the front is 5 inches off the ground while the rear is 4 inches with no height adjustment yet.

every small pothole doesn't jolt as if the passenger suspensions come rambling apart anymore yet.



Leaky old Strut.



Newly installed China made strut

 

Where did you buy the "China made" strut?