If any member can guide me into solving this electrical issue, I would greatly appreciate, it. The switches appear to be okay, the issues appears to be a short somewhere and I would like to know the best way to begin.

 

Best way to begin?

State the year and model of car and describe the nature of the problem you're trying to solve

Cheers
DD

 

1986 xj6 Jaguar.
Several weeks ago the sunroof and all window lifts no longer work. I am trying to find the electrical fault, I removed the switches from the center console, and they are ok. I suspect I have a short or fault somewhere in the wiring harness.
Is their a process, that someone can walk me through on how to proceed.

 

If everything stopped all at once there are two particularly likely culprits:

1) The defeat switch in the center console has been engaged, is broken, or became disconnected. Try flipping the switch and see if everything comes back to life

2) The relay that powers-up the window and sunroof circuits is faulty. It's on the extreme RH side of the dash, up rather high, outboard of the right side of of the glove box. The relay, if still original type, is round and black. It can be replaced with a generic 'ice cube' accessory relay. If you have a test light or meter we can provide some simple circuit checks.

Downstream of the relay the circuit branches off into two circuit breakers....but it seems unlikely that both halves of the circuit would fail simultaneously.

Cheers
DD

 

Doug
Thank you for your quick response. The failure did occur all of a sudden, and I will check both the defeat switch as well as the relay you referred to. I do have a test light and meter any simple circuit checks would be appreciated. I will let you know tomorrow afternoon if I was able to find the problem
Thanks again
Jim Jam

 

At the relay:

white/pink wire = 12v with key 'on'
brown wire = 12v constant
black/pink wire = ground (the defeat switch makes/breaks the ground path)
red/slate wire - 12v with key 'on' (output to the two circuit breakers)

Cheers
DD

 

Doug
I flipped the defeat switch as you mentioned, no change
I checked the following wires that you suggested and are as follows.
The brown wire lit immediately when tested.
The white/ pink wire lit upon turning "Key On'
The red/slate wire did not light with key on.
Also I tested the two wires coming off the defeat switch and the test light did not light.

Any other suggestions
Jim

 

Good



Either the relay is defective or it is not being grounded


This is a ground circuit so, just to be clear, did you have your test light configured to check for ground?

Ground the black/pink wire at the relay. Use a jumper wire or similar method. If the windows now work, you know the relay is OK and the problem lies in the relay ground circuit.



Cheers
DD

 

I read this on my ancient lap top yesterday. I don't type well on it. so, I delayed a response for today.


Doug beat me to it !! Got similar conclusions to mine. Bum relay or connections.


Good sleuthing. Fault found. Huge accomplishment.


Fix amongst the simple. If the usual Jaguar Mantra fails, the alternative is not a tough one. Mantra. Clean, tighten and lube all connections.


WAG: Jump the ground leg connection at the "defeat" switch to a good known ground. Try the roof and windows.


If still, no go.


On to a replacement generic relay. Think function. Load leg and its connections. Trigger leg and its connections. Many generic "ice cube" relays are so labeled. I like the term, "ice cube". Although, most are black rather than clear, the size and shape of each are so similar.


HAPPY NEW YEAR to all. My Black Eyed Peas are soaking for the 1st's meal. I'm thinking, ham, peas, a nice bread and a composite salad. Hearts of Romaine lettuce, tomatoes, onion rings, avocado and dressing of choice.


Oh, me, I can not hear. Home remedies failed. So, off to the Doc's in 2018. But, I manage.... With the help of two smart kids !!!


Carl

 

Doug
I clamped my test light to a known ground and touched the defeat switch with the pointed end of my test light to one of the wires on the defeat switch. My test light lit and I heard my relay click. I than operated one of my window lift switches and the window opened and closed.
Thank you. The problem appears to be in the relay ground circuit.
Not really familiar with electrical wiring, can I just leave a "Jump Wire" in position or is there a better process, to eliminate this problem
Thanks so much for your help.
Have a Happy New Year
Jim

 

Carl
Thanks for your reply.
Knowing my relay is good, and after jumping the wire, I just need to figure out next step, Doug has been extremely helpful.
I appreciate your thoughts as well
Jim

 

In this case, yes.

Cheers
DD

 

Doug
Thanks for your help in resolving this issue.
Jim

 

I am a bit reluctant to type this. As fixed is fixed. Elimination of the "defeat" switch by jumping it is not uncommon. If you have no small kids riding in the back seat to cause mischief, all the better.


However, you might want to test the switch.


1. Continuity feature of the VOM. Hook up. flip. On/off as to continuity?


2. Remove and bench test. Use a 12 v source and a test lamp. will it turn the lamp on and off?


I suspect the switch innards are corroded. It can be opened, I think.
Clean the contacts and if nothing is busted, it should work


Alternate. A good used or NOS from David Boger at Everydayxj. Good guy, good stuff at reasonable prices.


Another Jaguar Mantra. When electrics go nuts, check out the grounds.


Victory is sweet, huh!!!


Carl