Hi,

Does anyone know where I can get a new or nearly new relay as mentioned above?

I have a '96 XJS with badly behaving headlights!

Thanks,

Andrew.

 

Try forum sponsors SNG Barratt:



Graham

 

Try here - Grublogger recycled Jaguar parts - instruments & switches

 

ebay has a couple not silly money either

 

That's great, many thanks.

At that price it might be worth a try, cheaper than an hours labour at the local Jaguar dealer!

Out of curiosity when XJS owners have experienced issues with the headlamps is this little trouble maker usually the problem?

I have no side lights, I have low beam, but when I switch to high beam all the other lights go out. Including the dashboard lighting which is odd.

 

You might have a bad headlamp module but I would suspect some other things first. For instance, having no sidelights is odd as they are not controlled by the module. Before spending the cash, I would look at the headlight switch on the dash, inspect/clean it and test the outputs as you change switch position (operate high beam too). Also check the wiring to the headlamp module in case you have a short or bad ground.

The dashboard lights also bother me, after checking the switch, have a look at the dimmer control module which is under the dash, a faulty one caused all kinds of weird lighting problems on my XJ6.

 

I had high beams and very dim low beams. Driving lights would not work. Unplugged the headlight module and spun it 180* and touched it to the harness. Everything worked... Ordered the replacement from SNG and everything functions correctly.


Good luck!

 

Thanks for replies. All helpful.

Thanks Allan. Yes I did wonder if maybe it might be the control stalk itself. Which then in turn might wire through the dimmer as well.

When the issue started. It was the instrument lights that flashed on and off a few times. So could be the dimmer. Might be possible to bypass completely maybe. Just to check.

 

Tried DenverDRS suggestion and yes the headlights do indeed come on now.

Once I've tried a new relay I will update this thread to give an update.

 

Hi again,

Oh well, I managed to get hold of a new DAC6902 Module from SNG Barrett.

Unfortunately the problem has not been solved so it looks like a trip to the local Jaguar garage to see if they can figure out what's wrong.

Fingers crossed it won't be too expensive!

 

Let us all know what the result is, mine are weird too; sidelights, and main beam ok, no low beams (on a twin headlight set up).

 

Yes, as I mentioned above, it could have been the relay but I doubted it. My money is on the lighting switch/stalk and/or wiring/grounds or possibly the dimmer switch. It should be pretty easy to diagnose if you have a multimeter and a heck of a lot cheaper than going to the dealer!

Download the electrical guide from the sticky section and just work through the circuit, it should not take long to find the culprit

 

Just had a quick look at the wiring diagram, If your multi-function unit is working (the thing that chimes when you put the key in the ignition, or chimes to fasten seat belts) just turn the side lights on with drivers door open. You should hear the warning chimes for lights "ON"

If not then that really does put the focus on the switch or the white connector that is next to the steering column..

If you do hear it, then the switch and connector are good and you can focus elsewhere. Have you checked the actual headlamp and side light relays? They are different from the headlamp module. A bad headlight relay would cause the no headlights condition but the high beam flash would still work as it does not go through the relay. It would be a simple job to either jump the relay or swap with a known good one (it is one of the blue (or black on later cars) relays that are used all over the car. The sidelight relay is next to the headlight relay.

 

On the diagram it shows individual fuses after the relay and fuse box; are these buried in the loom somewhere?
My lights were fine until one of the (twin light conversion) inner sealed beam bulbs went. Rather than fork out a lot of money for a single sealed beam unit I spent a bit more on 4 new halogen ones and now I have no power to the inners.
It's not the relay as I swapped that out with a good one and there was no change.
I got so fed up with it that I went and bought an XJRS!

 

A triumph of hope over experience?

greg

 

Know how sublime a thing it is to suffer and be strong.
Longfellow

 

Sorry for the delay in getting back. Been a bit busy with work.

I did think the stalk switch next on the check list.

But as mentioned above when you switch the light stalk to "side lights" there is nothing not even the instrument lights, BUT the lights on chime does come on when you take the keys out of the ignition with the door open. Which in theory would eliminate the stalk being the problem.

The instrument dimmer works fine.

The bit which concerns me is the behavior when on driving lights. Why would all my instrument and side lights go out when selecting full beam? That I would imagine points to a damaged wire or bad earth. And although I'm ok with car electrics (managed to sort most of the problems so far) ones like these are a major pain! haha.

Maybe it's something simple like a corroded bulb maybe? The sun is finally trying to shine over here on Guernsey (after the wettest winter in 200 years!) So might be able to attack the issue tomorrow. The bulbs are still the originals on the car.

Thanks again for everyones help.

 

A little update for you.

Booked the car into my local Jaguar dealer to see if they could at least pin point the issue to help me solve it (couple of other issues as well.)

The basic story I got was as the car is very old they can't help me.

The diagnosis computer has pinpointed a short in the wiring loom between the switch and the headlamp assembly but to trace the fault was going to cost me £400 in labour.

They have no wiring diagrams for the car ("it's too old Sir".)

So not surprisingly I've had to leave it! I will try testing parts of the circuits at the weekend and swapping out the relays as suggested to see if I can figure out which side of the circuit is faulty.

I do have the wiring diagrams from my Jaguar DVD so I will try my best to figure it out

 

Andrew it's very easy to troubleshoot the circuit.

First remove the headlamp relay (not the DAC6902 module). Then with a voltmeter do the checks outlined in green on the relay base. If you don't have 12v then you must trace back along the circuit

If you have 12v then using a bit of wire or even a paperclip, jump the relay base as in the pic attached, do the part in red. The headlamps should come on. this will prove if the relay is faulty.

If they don't then do the part in blue. And then keep going along the circuit until you find the problem.

 

Hi Allan,

Many thanks for that, really helpful, fingers crossed for a sunny weekend and I'll get onto it.

I guess it's fairly lucky that the engine bay is laid out like it is, at least you can check one stage at a time fairly easily.

I've managed to find a few shorts in the system before and on other cars so I have a bit of experience with this sort of thing, fingers crossed!