Hi, I have had a look around the forum and seen a couple of similar posts with people having similar problems, but nothing quite as in depth as mine. Any help would be greatly appreciated.

My 2004 XJR has an intermittent problem where the NSF Xenon Headlamp goes out.

All other lights work, there are no warning lights and no fault codes recorded.

I have tried the following :

Replaced Both Earth points behind the headlights.
Replaced Both D1S Xenon Bulbs.
Replaced the Headlamp ECU or "burner" underneath the NSF headlamp.

it doesn't matter if the lights are manually switched on or the "auto" function is used and it even occurs if the lights are switched on using the fob.

I am completely at as loss, both times it has been into the dealer the lights have been working and no faults found.

Any Ideas????

 

Swap the headlamp assemblies and see if the fault changes

If it does its the lamp, ballast or internal wiring
If it does not swap its in your wiring, check the signals and trace back

Cheers
34by151

 

Thanks 34by151,

That would make sense to see if the wiring inside the headlamp is at fault or potentially elsewhere. Jaguar themselves told me today that the car has a headlamp control module which they think is under the bulkhead somewhere near the pollen filter?? This sounds a bit strange to me, but it's booked in for an expensive "diagnosis" on Tuesday. I haven't heard of a headlamp control module and nothing comes up when I Google it. Guess I'll wait to be educated!!!

 

Its driven by the "front electronic module" or FEM to 3 relays
This is located the in kick panel under the on the drivers side

R5 Dip beam relay "High beam" (fuse F9)
R6 Fog lamp relay (fuse F18)
R2 Main beam relay (fuse F16)

Look in the front power distribution box (near the headlamp)
Try a swap of R6 and R5 to check if it the relay
Check the fuses

The HID ballast also has separate power
LH lamp uses 38ii and RH uses 39ii so this may be the answer
Power is supplied to this from the passenger fuse box F3
It wont be this fuse but may be wiring as both have the same fuse

I'd make a bet though its the ballast though
See here https://www.jaguarforums.com/forum/x...-lad5gl-89738/

and

here https://www.jaguarforums.com/forum/x...60/#post803085

Cheers
34by151

 

Thanks again, i've checked out what I have the limited ability to check, Relays and fuses seem good - problem still present. I think i'll have to succumb to the main agent!!!

 

just an update : Car has been to the Main Agents in Stoke on Trent who say they can find no issues with the wiring, modules or fuses, earths or anything else, (the replacement ballast I put in is flickering and so the original one needs to be put back and this one posted back for a refund), and so they say the fault lies with the Headlamp unit. £750+VAT !!!!! I have found a second hand one from a reputable Jag Breakers for £225 so will try that. If it's not that I am not sure what to do. I have noticed that the light will turn itself off more so when it's warm. I wonder if something is expanding/contracting and causing an earthing issue in the light unit???

 

The lamp can flicker if it ts the ballast or the globe
You really need to swap over the headlamps to be sure

You may also have an issue with the light sensor ore the stalk but if you are only getting this on one lamp its not likely
Try using the lamps set to on rather than auto

Assuming the fault does not change and you swap the headlamps over it will be in the harness supplying the headlamp

If the fault swaps with the lap it will be either the lamp, ballast or wiring in the headlamp
All of these are repairable

You need to take the bumper off to remove the headlamps and I doubt the dealer did this for you
Unless the headlamp is physically broken you don’t need to replace it

Cheers
34by151

 

Ok, fingers crossed the fault is found - you're not going to believe the result!!
After Stratstone Jaguar in Stoke diagnosed the fault as a headlamp unit, I ordered a second hand one andfitted it. The problem was still there. So much for main agents!! Bad advice and money wasted. The second hand light unit came complete with an old D1S bulb, which we removed before fitting to accomodate the New 8k D1S' I had bought. I thought I may as well try the bulb that came with the second hand light unit, guess what? NO PROBLEM! So assuming the problem doesn't re-appear, it's been down to a faulty bulb, which was replaced with a new one which had the SAME fault on the SAME side! I never guessed a new bulb could be faulty like the original, and I have no real resources to swap headlamps/bulbs over side to side. I guess the lesson is DON'T go to the main agent as they simply dont have a clue.

 

34by151, dont say it! "You told me so!"

 

Glad to see its sorted out

Cheers
34by151