Xj caught fire. Now where to start

Looking for a bit of assistance with wiring on a 90 AW4 4.0 renix Xj.. Nosigma, you may be one of the deepest divers into this
Last week I get a call from my son while Im at work to tell me my Jeeps on fire. :flame:#$@%^ he did do a great job putting it out minimalizing the damage

so I get home, to find the left 1/4 of the dash and melted mush of plastic and everything coated in extinguisher powder. I walked away..

I go out to day and hose off the powder to evaluate whats there. As it looks, the ign. wires are good.. most the wires that run on the floor look ok, but are encrusted in melted remains. now the wiring to the left of the column, thats another, crappier story. As it stands now it looks as if either the dimmer switch or a little metal box under this area( mounted to the underside of the dash near wiper control box) was the culprit. Not sure why either would go though.

So all that being said, what in the dash can I abandon in place? I cant pull the dash, no way to do so. I can pull fuses I can crawl under the dash, I can cut up whats left to get behind it. What do I need to make it a functional rig. I havent safed anything off yet. Battery is disconnected
as luck would have it I have a stock 94 manual 4.0 to look at for most reference items..
Any help is greatly appreciated.

I have several short dash harness from where I bought a few dash from a jy. They were shortend by the guys that pulled them. You could splice it into what's left and solder and heat sink everything. Even if you have never soldered before you would be a pro by the time you were done. Dash has to come out so plan on refreshing heater core and evaporator while you are in there if not fresh.

I cant pull the dash

What do you mean, can't pull the dash? It's plastic right? Melted plastic hardens back up. Which means it can be cut. Head to the JY and find a donor. Take everything. The whole dash, all plastic, etc. It's not as many pieces as you might think. I would pull the entire dash harness and all associated junction blocks/PDC's as well. Splicing would be just as much work, and you don't really know what condition the harness will be in- could end up being more of a headache down the road.

In regards to your dash- get out a grinder, sawzall, dremel, and get to work. Cut the whole thing out. Swap in the new donor wiring harness and dash.

Whatever you do, I would be evaluating the monetary, as well as emotional/sentimental value of the rig as a while. May not even be worth saving if a replacement is cheaper. Remember time = money. And this will be a headache of a job.

The cage is preventing me from pulling the dash.

Sounds like a start over to me. That really sux.

cut out the cage.

Make a custom dash can you weld? Aluminum would be cool maybe some beed rolls.

cut out the cage or cut out the dash. You really don't want to leave a melted harness in place unless you can completely disconnect it.

hoping to tear into it this weekend. Long hours at work the last 2 weeks and Easter havent alotted much time to mess around.
I can cut weld or what have you. Also have access to talented fab guys but it would be easier to drive it rather than drag or winch it.
My first goal is to clean up what I can tell of the wiring that isnt "run" necessary. Then I can rewire and install what guages etc that I want back in there.
I should mention this is TRAIL only, I have no interest in cutting the cage out.
I dont need OE functional lights( most are either removed or broken as of right now anyway)
I appreciate the comments. Ill take all that come this way.
Thanks!
:cheers:

Ahhh, I wasn't sure.

I'd rip the dash out either way. Assuming the AC doesn't work and the heat does, sorta?

The only thing you probably care about wiring wise in the back is the fuel pump. Gonna need ignition switch and brake light switch in the steering column area but that's about it... speakers/radio? Care about those?

Actually it all worked. Heat A/C, the whole lot.
My arb and oba switches are in the dash but thats not to big a deal. I can relocated them all. Im just focused on what makes it run and drive. The trans module looks fine. The box where the wipers connected not so much and there is a little metal box that I have no clue what is was or is for. That acutally looks like it could be a source of the ign. I wont know until I really get it. Unfortunately it was cooled before I could get my IR camera in to check temps

Quick update. Got to mess with it today.. Looked worse with all the melted bits all hanging down and covered in fire extinguisher goodness. so I hosed it down a bit, vacuumed out the rest. Got to cutting some of the dash trim out, removed what was left of the gauges and got to snooping around. Bad news,As I got to looking around, the harness connector for the wipers was melted but looked like collateral damage. The light switch was too and after pulling what was left of it and looking at the harness I cleared that of any issues. The dash trim and gauges on the left side of the steering column(tach side) were pretty toasty too. Again collateral. So as I dug a little more. I found 3 possible culprits 1- the defrost switch 2 the fog light switch 3 the fog light relay( behind the switch) The heat source was definitely from that area.
I isolated the fuses for these items: Lights ( any in the jeep, as if you know my jeep it doesnt really need them) gauges( I will replace once find new ones) wipers, radio, and well everything not associated with the pure function of the Jeep. Kinda like a 2a..lol
I clipped the burnt up connectors and isolated the wires coming from the harness to them. Then cleaned up a few wires that had crusted from heat. I had already disassembled the turns/wipers/cc from the steering column
Now I have a new to do list:
> find new gauges
> find new trim
> install battery cut off switch - this will come in handy later
Re assemble

Then back to why my damn brakes dont work....

Are you absolutely sure that's where it came from? As I recall, all those switches are in the same general area and above the high beam switch and ignition switch on the steering column. Might be wrong, though, been a while since I was under a 94- XJ/MJ dash.

yup. well 99.9%
The high beam switch was already disconnected. The ignition switch is off the column and clear of the area, also all wires and connections related to such we clear. In looking at the area the ONLY areas severely burned were the ones mentioned to be culprits. The only thing I cannot determine is why. Defrost would have turned off once ign was off. I suppose that since my headlights are out, that my headlight switch could have been left on, and I might have bumped the foglight switch; which in turn may have been shorted somewhere down the line( never had issue before) and thus heated and subsequently burned

Yeah, that's really weird.

Well. I don't know if a '90 is like a 94 or so (same steering column... but RENIX vs OBD1 and a lot of harness differences) but the same fuse runs the rear defrost grid and the starter solenoid/relay on early 90s XJs, so that circuit may be energized even when the vehicle is off.

I know that 93- have a fuse/relay distribution block near the column and a few extra connections that the pre 93 doesnt. I have a 94 (man) here to look at