Without having the car in front of me it's hard to guess where to start, but you might try disconnecting the + lead to each fuse box beginning with the one in the boot, then progress to the heelboards and the engine compartment.

Anyone out there have an opinion on the logic of this?

 

I see two multipin connectors that may help isolate the short, but I don't know exactly where they are and I wouldn't want to take the dash apart looking for them.

FC4 20 way blue drivers side underscuttle
FC7 8 way white passenger side underscuttle

Can anyone interpret that?

 

Thanks for all the helpful info, RJ237! Pulling the 10 amp fuse in the left heel box ended up working for me (confusing, it's fuse #2 going in a row, not left right left right) after pulling a few wrong fuses and draining the battery again...

When I get the car started I'll look out for that burning smell. When I'm not busy with school I'll pull the console and check for the ground / maybe a short, and pull the relays too. Will that have a different effect than having pulled the fuse?

Thanks!

 

You have found the problem, it's the illumination dimmer fuse. No need to look at other fuses or relays.

If you have downloaded the 1995 electrical guide from jagrepair.com look at page 115 and start tracing the wires from connector FC4. This may not be a fun project, but I can't think of an easy way to locate the short.

I'll keep thinking, and maybe one of the members who is better at this sort of thing will be able to help.

 

Thanks, I'll take a look! I'm guessing it's behind the dash so I'll start by pulling that all off (and give it a nice wash while I'm at it!). I'll look at the diagram and see where it connects to that. I'm still going to check the earth connection because it was flickering before the problem of it staying on arose. I'll keep you all updated- please feel free to reply because I'm still not sure exactly what I'll have to do.

Thanks so much, I mean it!

 

Hi
I hope you have made progress....... I did come across this Jaguar X300 TSB that relates to interior lights remaining on.......
Here is the link
I hope it helps you out

http://jagrepair.com/images/TSB/X300...20Lighting.pdf

 

Haven't done anything yet, besides a fresh oil and filter change!

Wow, reading this over- these are exactly the problems I was having. Might explain the speaker crackle too. Thank you so much BigBoss!!

When I have time to do everything I'll make sure to let you guys know! I'm feeling rather hopeful now, though

 

It's curious the things that are buried in the Official Jaguar XJ300 TSB's
It sounds like a good place to start.......

I hope it helps you out.

if you need to remove your radio you will need to remove the Ski Slope. I think there are directions and pictures here or at the jaglovers forum.......

 

Here is the link to the thread here on how to do it

https://www.jaguarforums.com/forum/x...300-faq-57038/

 

Thanks for all your help Big Boss. I plan to tackle this soon but I've been caught up with school... I really appreciate it guys. Hopefully it will be something simple otherwise it seems I will be stuck pulling that fuse or disconnecting the battery every night!

I am honestly lost here, I knew what kind of electrical gremlins to expect with the car but this seems to be a little mystery of its own! At least she purrs neatly still!

 

So a little bit of a refresher here:

I recently rewired my entire boot, and it went pretty well besides looking messy with the butt connectors now. That got me thinking of what the problem could be with the lights--I've gotten so used to just pulling the fuse every time I park that I haven't thought about fixing it for a while.

I noticed that when the car is parked (for maybe an hour to two hours max), there is a distinct plastic/electrical burning smell from what seems to be behind the dash. This leads me to believe that the relay has "soldered" itself to the on position, which would explain why it was so finicky before, flickering all the time.

Well, I figured I'd check the wiring diagram for the car so I wouldn't have to bother everyone here again... the only relay I found in the diagram that was under the same section as the interior lights in question, was the relay for the driver's side puddle light. Other than that, it mentioned the wires in the steering wheel and light control box. What am I missing? I don't want to rip apart the interior only to find that I have no idea which relay it would be. (I suppose it could still be the ground, too, but still)

Thanks everyone... hopefully this chapter will be over soon. It's a very, very weird problem.

 

Nope. I am just stumped too!
However, since Malhide seems determined to find it and it is clear he is not going to throw in the towel and start complaining about the Jag's design, I will offer some suggestions. Since you probably do not have a clamp on DC ammeter, try the old "series shunt" method of putting a headlamp or other higher power load in series with the battery positive lead. It should illuminate dimly. Then pull out and replace fuses one by one until you find which circuit is the offender. Post back and we will go from there. If no fuse turns off the light, that is also good info.
I assume you have a test meter of some kind. What is its maximum current measuring capacity for DC?

 

Ross- earlier in this thread we identified the illumination dimmer fuse as the one supplying power to the shorted wiring. He has been pulling that fuse to stop the power drain.

Then, in post#26 BBR supplied a link to a jagrepair.com article with a TSB link.
That may be useful, but I think Malihide hasn't gone any further with the search.

 

I guess I should have read more carefully! TSBs generally have a purpose and that one sure seems like it has merit for these symptoms. I would be very hesitant to continue installing the fuse and driving given the smell report. We electrical engineers cringe at the faintest smell of burning insulation because it many times is the immediate precursor to sparks, meltdown and flames, even if protected by a fuse. The fuse is meant to protect the circuit from getting hot once. Not to continue protection time and again.

 

RJ, I have looked at the TSB--when I take out the ski slope, I will be looking behind the radio as well as looking for the ground. I was hoping that would be avoidable if the relay is located elsewhere, as I think it could be stuck 'on.' I read the wiring diagram and it wasn't clear to me where the relay would be located; excuse my inexperience. If no one knows where it is, I'll just have to dismantle the ski slope.

Ross--could it really be dangerous? The smell only happens when the car is off and the illumination switch is set to "off". It doesn't happen when the switch is on and I'm driving, which is why I thought there was a problem with the relay, but I suppose this would be more indicative of a short to the ground since the dash lights are on dimly?
It just occurred to me that this means when it is shut off, the current is not traveling through the dimmer switch, as that is set to maximum. I'm thinking out loud here, but does this mean anything?

I guess I'll have to take it apart and look. It would be nice to know more possibilities of what it could be, just so I don't get stuck driving around with my centre console dismantled!

Thanks a lot, everyone.

 

The problem with wiring that is burning is that is almost certain to get worse, assuming it is the wiring in the TSB. Insulation melts, wires contact ground, wires get hotter as more current flows - more melting, more conductor contacting ground, more current.
So, no, I cannot guarantee a meltdown if you continue to run it, but I can tell you there is significant likelihood of additional damage . If it smells, something is hot. If it is hot, it is probably melting something- that is what smells. If it is melting, it is BAD!

I admit it is a puzzle as to the problem happening only while stopped. That does not seem like symptoms of a relay, though. Maybe something like the antenna wire shorting? It runs the antenna down when the car stops. Or- if two wires are burning together, then if both are on for running, and one is off for stopped and the other remains on, you have a voltage difference that can flow current? Just wild guesses, but it will be interesting to know the real cause.

 

The problem will happen when the car is on, too, I should have been more clear; the thing is that I only plug the fuse in at night while I'm driving, and therefore the light switch will be on, too.

Antenna wire? Maybe... but I haven't had a single issue with the antenna thus far. It actually surprised me when I got the car, because it works flawlessly. Sigh... I'll have to get back to you guys when I have time to take the ski slope out, it seems. I'll try to do it today. Thanks guys!

 

I was not clear when I used the term "antenna wire". I meant the wire that tells the antenna to retract! A log shot, but it matches the symptoms, I think.

 

That's what I was referring to, as well. I was surprised that it retracts after all these years. No problems there... I haven't had a chance to go out and remove the ski slope, since I have a few upcoming tests to study for.

 

Update:
I spent hours removing the Ski Slope and checking for the supposed frayed wires. Clearly, they have been repaired as per the tsb; wrapped in thick tape and tucked away. While I was there I checked both grounds and attempted to fix the clock (no luck). I looked for any sort of bad relay or short but I didn't see anything unusual, but then again I'm not exactly sure where to look. I reassembled everything and still had no luck whatsoever. Picture is of the wires mentioned in the tsb.

Is my only option to tear apart the dashboard and maybe the steering column now? Does anyone know where the relay is located? I checked the wiring diagram and couldn't figure it out.

Considering mickeying some sort of rig to just shut off the fuse when I lock the car... I'm getting sick of bending over every time I park at night!

Thanks for your helpful suggestions everyone!

EDIT: Looks like this was post #100 for me! It adds up fast! I hope my next few repairs will give me some insight to give back to this amazing community!