Power windows don't working
 

Hello ... A Dane asks for help!

Electric windows on my XJS 1984 LHD have stopped working at the same time. There is no power on rocker switches, nor electricity on thermal relay. Can't find any fuse and it's almost impossible to follow wires from Thermo-relay to find a possible fault.

Is there maybe a wise person who can help me???

Does the central locking and door mirror function?
I think that they are all controlled by fuse 7 or 8 under the right hand side knee pad - below the steering wheel on a right hand drive car.

Yes, door locks and mirrors work. I have checked all fuses, no one is faulty. Cannot find door windows over fuse table. Neither in the instruction book or workshop. There is no power up to the relay. Has tried to follow the lead, but it disappears under the carpet under the center console. There are really many wires there and I would like to avoid stripping the cabin altogether.

Your post is hard to read; are you copying and pasting in?
Mine does that sometimes.

Let's get our nomenclature clear. There is no "thermal relay" in the window circuit. There is a "thermal breaker", and also a "power window relay".

So, the thermal breaker gets its power directly from the right terminal post. Unless your have a loose connection or something else wrong with your right terminal post, the thermal breaker should be getting power (it's not fused).

The power window relay gets power from two sources, the thermal relay (#30 connection on the relay) and the ignition feed (#86 on the relay).

The power window relay is on the back side of the right component panel, which is underneath the passenger side dash. The relay has four connection. You should get battery voltage on connection #30 (one of the two brown/blue wires that go to the relay) all the time, and you should get battery voltage on connection #86 (white/pink wire) when the ignition is on.

A good place to start is the brown wire that goes to the thermal breaker. If it doesn't have battery voltage on it, that's a problem. If it does have battery voltage on it, check the brown/blue wire that connects to the other side of the thermal breaker. If there is no battery voltage there then the thermal breaker is likely bad.

With the ignition on, pin 86 on the power window relay should have battery voltage. If it doesn't, your problem lies somewhere before the relay. If it does have voltage, check pion 85 on the relay (again with the ignition on). It should have battery voltage. If it doesn't, you may have a bad relay.

One other possibility is a broken ground. Pin 85 on the power window relay goes to ground. If you don't get any continuity between the numerous ground points and pin 85, then the ground wire is defective.

If none of the above works, I would think you have a disconnection between pin 87 on the power window relay and the window switches.

Sorry for the long replay...just trying to cover as many bases as I can!

Thanks,

John
1987 XJ-S V12

Thank you. I think you give an understandable explanation.

Thank you!
 

Hello John.
The fault was in the relay. I replaced with an ordinary light relay from Hella. I first messed with a red relay, before I realized it was a relay for interior light. The right relay I found with help of a mirror and a flashligt. not a very easy location. Typical for older English cars, The electrical equipment is thrown in with a shovel. But very many thanks for your good help!

Regards Per

Welcome to the forum Per,

I don't think they were as technically advanced as that! :icon_lol:

I've removed the strange source .codes from your first two posts. You appear to have fixed that problem with subsequent posts.

Graham

Per,

You are quite welcome!

Cheers,

John