91 Sport blowing fuse

[ops5]

Hi everyone,

I have a 91 Sport that has been having some recent problems blowing the fuse that handles the tail lights/instrument panel/parking lights/Lights on chime. A couple of months ago, this fuse blew, and I replaced it. Everything was fine since until about a week ago; now everytime I pull the headlights on the fuse blows. This happens at the first stop of the pull for parking lamps, with the ignition off. I have not changed anything, such as the radio, and I have manual locks and windows. The brake lights continue to work with the fuse out.

Any ideas how to track down what is causing this?

Thanks,
Phil

[wayneo69]

check the headlite switch and connector and the high beam switch/multifunction switch and connector may be melted

[citizen@large]

Please stay tuned kids and fasten your seat backs into their full upright positions... The CPS has got to be the culprit here I tell ya!

I'm Kidding.

Aloha, please come to the lobby...

SWEET! I got my 3rd star! Yay!!!

[ops5]

I'll inspect the switches for the headlights and the multifunction switch tommorrow afternoon

[sector95]

Phil,

Well you've sort of done some troubleshooting already: the fuse blows when you turn on the parking lamps. This will turn on all your dash lights and all your (duh) parking and marker lamps. First thing I wold do is check every lamp on the outside of the vehicle that is supposed to come on in the parking lights position. Remove the lens covers and check for water/moisture contamination and corrosion....clean any socket that looks crudy and give em all a shot of WD40. Check the condition of the sockets and replace all the bulbs as you go through the check. Try to look underneath the vehicle and see if there is any cut insulation on the wiring immediately leading to the bulb socket.

I doubt it would be anything in the dash since you indicated you'd not done anything (aftermarket stereo, etc).

Does your Jeep have trailer hitch wiring? If there is a harness make sure those wires are not shorting out or the plug end is not grounding to the chassis. Even if your Jeep doesn't have a hitch, the previous owner may have had one on there and removed it (or the dealer removed it) but left the wiring stuffed up under the bumper. If you find a harness w/o a hitch and you don't plan on towing I would remove the hitch wiring.

Hopefully you'll find it's something simple like a bum bulb or socket or moisture.

Good luck....

Mike
00XJ

[ops5]

Hi Sector, thanks for the input-

I haven't really had a chance the last couple of days to look at it, hopefully tomorrow. I have replaced most of the parking lamps, with no luck on curing the problem. Two of the sockets had some old dried electrical grease that I scrapped out, the others looked pretty good. I'll look at the wiring and headlight switch in greater detail.

I do have a hitch and wiring- the connector is pretty dirty, I'll try cleaning that.

I'll update if I figure anything out

Thanks

[AlohaBra]

I used to use a tester from Snap-On that is a circuit breaker with an amp/inductive gage. When you hold it over the wire it tells you which direction to go in to trace a short to ground condition.

Since, I have stopped working at dealers, I have rarely run into a short to ground condition. It is kind of a guessing game. You can disconnect the harness from all the park lights all at one time. That would seem the easiest first step. If you fuse does not blow, then plug them in one at a time. Otherwise, keep looking at the other areas including the light for the cigar lighter.