I have a 96 XJS with the 6 cylinder engine.

Since I bought the car, the light on the passengers side door doesn't work. It's a minor annoyance, and one I attempted to tackle today.

I'm not particularly strong reading electrical diagrams but here's what happened.

1. Pulled out a multimeter and confirmed no voltage reading at the 2 wire connector going to the light socket. (door card was removed)

2. Went back into the car and, using the Captain Jaguar wiring diagram, found pins 8&9 on the 20pin sumitomo plug. Those two pins managed to be consistent with the wire colors in the door (purple And purple with white stripe). I found no power there on the multimeter still set to voltage.

According to the wiring diagram, I now have to find Bulkhead Harness Splice Connector LBS55 and LBS56. What is that? I don't know what I should be looking for.

Am I correct that the problem has to lie somewhere between the splice connector and the 20 pin block I tested? Everything else connected to the splice blocks work, so it couldn't be anything past that, could it?

Thanks!

 

It is a splice in the harness, it may not necessarily be a molded connector per se. It is hard to know where it is other than it is in the bulkhead harness. I would expect that LBS55 is very close to the interior light relay which is under the drivers side dash panel. Follow the purple/white wire from there until you find the splice point.

The splice at LBS55 is for a ground connection, however, so the door open, pin 9 on the sumitomo you found, should go to ground if you check resistance. It would be open circuit when door is closed.

And just to make sure I'm clear, you are testing with the door open right? Also the driver's side door lamp does work if that door is opened?

For LBS56, I'd start at the BN5 connector (20 way sumitomo) which is under the right side lower AC vent and follow the purple wire from there.

Good Hunting!!

 

Thank you, this is very valuable information.

I found the relay under the drivers side dash. I was thinking about tapping that line, pulling a new wire all the way across, and splicing into the wire just before it goes into the 20-way. I realize I'd have to cut the wire so that I'm not back feeding the old circuit. Would that work?

I would not cut any wires at the relay, I'd just tap into the wire coming out of Contact 87. I would then cut the PW wire just before it goes into the 20 way, continuing into the door. I would join the new wire there, abandoning whatever was going into Pin 9 at the 20 way.

That should either solve the problem, or isolate it to the purple wire?

I appreciate your help here. BTW, I am testing with the door open, and the drivers side bulb does light. I always check to see that the drivers side light is on when testing so that I know I should be seeing something.

 

First thing, have you done a continuity test for the purple/white wire? There won't be a voltage here, just open circuit when door is closed and ground when open.

If no joy there, then yes what you propose should work provided there is no issue with the wiring from the connector to the lamp.

 

Ok, so I pulled pins 8&9 out of that 20 way. I set the multimeter to ohms and I attached one lead to each of the two pins. I had an infinite reading whether the door was open or closed. Again, the remaining lights all work.

Then I tapped into pin87 at the red lighting relay under the drivers dash. I ran the same test connecting the striped purple to the lead from the relay. Same thing. Infinite reading no matter what I did.

I then connected a wire from the tap at the relay to the re-inserted pin 9 and voila! Light!

Apparently there is a bad splice somewhere along the PW wire. Thanks for the help!

Last question, do I need to cut the wire at the 20 way? It lit up the light without blowing the fuse. Is it better to cut it and abandon the old wire, or keep it and just short around it?

Thanks again!

 

Well my inkling would be to try and find the culprit, especially if it is a splice as it may worsen and affect the other doors.

If you don't fancy that hunt, I'd probably just that the wire out of the equation.

 

I poked around a bit, but those purple wires disappear rather quickly.

I ended up cutting the wire at the 20 way, so it is out of the equation.

Thanks again for the help!