electrical issue on a 97tj

[Hoodoo Man]

So yesterday while I was at work my wife noticed the lights on my TJ were on. She went over to the jeep and turned the lights off but the switch was not on. And she noticed there was a buring smell coming from the column area with a small waft of smoke. Now Im no expert but I think thats not normal.... Kris managed to pull the battery cable off to stop any further damage. When I got home I pulled the dash panel off and the column cover as well but could not see any obvious damage. Smell it, but not see it. I managed to jump start the heep and it ran rough and would not stay running at idle. after a few minutes running I didn't see any more smoke and then I had to go to a school function so I had to leave it be, left the battery cable off just in case..

I don't know if this is related but when I was out of the jeep while it was running I heard a vibration coming from in the fuse box and the fuel pump fuse was vibrating slightly but this may just be random.... given the rough idle it may be related but I don't know why a fuse didn't blow instead of smoking like it did...

Any thoughts on what to look at?

[del_TJ]

I'd start by checking if a relay is stuck on, and if so, whether it's shorted at the input or if it's just a bad relay.

[ASauer17]

Similiar situation happened to me about 6 years ago. I had to pull the steering column/lower dash and the wires were melted. I replaced the ignition switch and harness/wires. I had no issue with fuses.

[Kurt]

The headlights are fed by Fuze 10 30 Amps in the PDC under the hood. It in turn feeds the headlamp switch which internally has a 24 Amp circuit breaker.

There are no relays in the path to the headlights, just the fuze, headlamp switch and dimmer switch.

Battery ---> PDC Fuze 10 ---> Headlamp Switch ---> Dimmer Switch ---> Headlamps

From your symptoms it appears something has shorted allowing power to the headlights.
Could be another wire that got hot, metled insulation and shorted to the headlamp feed, possibly the headlamp or dimmer switch failed.

Electrical problems suk to locate

[Carl McFly]

Electrical problems suk to locate

......yup......

even worse than the elusive "Evap System Leak (very small)"

[zenophryk]

So continuing with what everyone else said, which I agree with totally. if you now have a short, wich may be caused by 2 wires melting together, or one wire melting and now touching ground, or one wire melting and fusing to another wire from a totally different circuit. once there's a short then a whole lot af different things can happen. one of which could cause the fuel pump relay to buzz. So the relay turns on, delivering current to the fuel pump, but if there's a short in that circuit somewhere (maybe in the steering column) then the extra load could be enough to shut off the relay, which removes the load which allows the relay to turn on, which enables the load and the cycle repeats causing the buzzing. the result of the buzzing is that the fuel pump will only be running at 50%ish so only delivering half the fuel pressure and would cause the crappy running you described.

So if Kris saw smoke then there's probably some melted wires somewhere, and something that caused them to overheat (could just be cracked/broken insulation from age, I have that on my 99) you have to find the damage. a good multimeter is a great tool to have for this.

I'm in nashua a lot (not far from westford) and may have some time to help you with it this fri,sat or sunday if you like.

-Chris

[schwalby]

Last time I had an electrical issue it was because the grill was no longer grounded. It caused the high beams to come on after awhile turn signals would not go off and turning the wheel any significant amount would get them to come on. Plus several other head light, turn signal issues.

No idea if that could cause your issues but I would also never think the grill not being grounded would cause the issues I had.