Air Suspension Fault Only with HID Headlamps OFF
 

Hey all, I have an 04 VDP and have recently changed out the front shocks to arnott's and solved some wiring harness breaks that were preventing proper readings from all the sensors, now the car levels out and rides like it did when it was new. A broken passenger headlight assembly was swapped out for a used one recently as well. Both HID bulbs seem to work fine.

Trouble is, when the lights are off (HID) then "Air Suspension Fault" appears on the dash. When they are switched on the fault clears immediately. The jaguar codes that come back say "headlight" in the air suspension fault section. And that's the only fault listed. I don't know if this was the case before, since it most always said Air Suspension Fault due to the wire harness issue. Thanks in advance!

Check the earth points behind the head lamps first be careful they are very delicate

Both the left headlamp and the air suspension compressor are grounded/earthed at the stud behind the left headlamp, so it would be worth checking the wires attached to the stud for any obvious problems. Remove the nut and wire ring/eyelet terminals and clean them and the threaded stud with a soft brass brush and zero-residue electronic contact cleaner. Allow to dry, then reassemble. As clifton94 warns, the torque spec for the nut is a very low 6.5 ft. lbs., which is not much more than hand-tight. Several members have accidentally snapped off the threaded stud by overtightening the nut.

Also, it would help us help you further if you can post the exact Diagnostic Trouble Code(s) (DTCs) reported by the scanner.

Cheers,

Don

Funny I should run across this today. I was pulling out of my garage (05 XJ8L) and the amber light came on and the Air Suspension Fault message came up, followed by "headlight not on" or something. I went to eat and when I left again the messages had cleared. I had thought it was an odd combination of things to come up at random, but this makes sense. I'll check that out first opportunity!

DonB, is this grounding stud immediately obvious or will I need to pull the covers off to access the rear of the headlamp area? Just got her this week, so not fully up to speed yet. Thanks!

adam

There are two ground studs directly behind the left light assembly and one behind the right headlamp assembly. They are easily accessible.

Be very, very careful when loosening or tightening though. pictures here:

https://www.jaguarforums.com/forum/x...lights-136236/