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Hi Guys, I upgraded my rear lights on my 1998 XK8, all worked fine for 6 months. The other day my 2 rear side lights on the N/S stopped working, and would only flash when I used the indicators, then one problem followed another....my drivers window stopped working,...showing on dash N/S door open, but was closed.....Fixed window and door open...found 3 relays were loose. Now my drivers window does not work...micro switch I think.....and seat belt light is lit even with seatbelt secured, (having fun here)....had an auto electrican out...but his equipment would not diagnose back to 1998...but he connected a wire from the boot fuse box too the rear lamp, saying there was no power going to the orange wire to the N/S ???? and now with this by- pass all my lights are working again, does anybody know if the lamp module could be at fault ??????
Does anybody know the correct wirering colour codes for my new rear lamps (wires to old connector).....Many thanks for any help !!!!....Tom.

Hi.

A burned or bad ground connector in the tail-light assembly has been known to cause problems. Adding an extra ground wire to the chassis have solved this problem.

If your door open light stays on with the door closed I would suspect one of the microswitches in the latch assembly.

I had a bad contact in the connector between the door and the car causing my window to get stuck. Opening the connector and spraying with electrical cleaner (not WD40) solved this problem.

A weak battery is known to cause multiple nuisance warnings.

Rear Light Conversion Wiring Changes (2000)

Righthand Side (UK Drivers)

Control Car Light/Plug
Indicator GREEN & ORANGE 3
Fog ORANGE ORANGE
Side Light GREEN & RED 1
Brake ORANGE & YELLOW 2
Reverse YELLOW 4
Earth BLACK 6

Lefthand Side

Control Car Light/Plug
Indicator GREEN & WHITE 3
Fog ORANGE ORANGE
Side Light BLUE & RED 1
Brake BLUE 2
Reverse YELLOW 4
Earth BLACK 6

Always disconnect battery when working on electrics. (Radio code)

Hi Oyster,
Many thanks for taking the time to reply, the wiring colour codes will be a great help,
Since I posted this notice, I have taken my lamp module apart ( once unplugged from car, the module just unclips apart )....found my light problem, 2 diodes had burnt out.
After checking for bad earths, I advise members to check lamp module first before calling an
auto electric guy out, unlike me, COSTLY.
Thanks again Oyster....Tom.

Hi again Oyster, As you look at the light plug from the top (connected)....which is slot number 1, 2 , 3 etc ???????. my plug has no markings, Thanks ...Tom.

There should be some tiny numbers visible with a flashlight and a magnifying glass.

Thanks for that , got them....Tom.

After a couple of days, my rear passenger side lights have gone off again....all other lights , indicators, brakes, reverse, are still working.....Checked light module again...all ok, Fuses ok, reconnected a jump wire from fuse box too rear light,...all working again...but now getting a light out warning on dash....really stumped with this 1......?????? Any ideas guys before I end up in Jaguar main dealer.... Thanks...Tom.

To have one electrical fault is unfortunate but to have had the series of issues you have experienced on your car does suggest that it's probably time to bite the bullet and book a visit to a good Jaguar specialist. These cars are a long way removed from their predecessors in terms of complexity and the usual difficulty is finding someone capable of interpreting the Jaguar diagnostics system correctly rather than simply changing modules until they hit lucky! Unless you know that a particular dealer has a good auto electrics technician, it might be as well to ask if anyone in your area can recommend a specialist similar to XJK or David Marks, both of which garages are excellent at resolving electrical issues. Mike.

Hi Mike,,,,Phoned David Marks...said try earth...if not that he had no idea...tried earthing all over, ...no difference. Does the body module have anything to do with lights ???? or any other part on car ?????? Tried 2 auto electric guys....Jaguar main dealer in Chester...still no joy...There must be some help somewhere lol...???????

Yes, the body processor module does control lighting. To give David Marks or anyone else half a chance, I think you need to let them see and test the car. Remote diagnosis of obscure electrical faults on these cars is not a simple business and unlike less complicated vehicles identifying failure patterns typically requires the outputs from the full diagnostics kit. Mike.