Weird headlight problem

Ok, the basics

1990 MJ

When I turn on my headlights, I get no parking lights or dash cluster lights. The headlights do work as do the brake lights. Along with the blinkers.

The 10amp park light fuse is blowing. Im really not sure why, nothing is added into that circuit, and I havent touched anything electrical lately. Witht he exception of new battery terminals monday, today is thursday.

Everything has worked fine up until now. I really dont know where to start. I was going to check grounds, but that wouldnt blow a fuse. where should I start with this?

If you put a new fuse in will the headlights work then blow the fuse or does it blow the fuse right away?

The *headlights* work all the time, no problems

Its the parking lights that blow the fuse

The park/tail lamp fuse should be 20A not 10A.

According to my FSM and fusebox its a 10 amp

Number 15 - "Park"

10 amp - Red

Headlamp switch, inst lps fuse, insturment panel lamps, clock, radio/clock illumination relay, rear lamps, front lamps.

Oh, my wiring diagram says 20A- park/tail, 20A- clk/haz/stop, 15A- turn/bu.
If you can get a multimeter in there and check the amperage. If you wana throw parts at it i'd say headlamp switch, if you don't have a F'd up wire or connector before the fuse.

replace any bulbs recently? do any wiring recently or messed around with any wires? I would think its something simple, just finding it is a pain. oh and do the parking lamps work when the headlights?

***nothing*** works with the headlights. I turnthe headlights on and JUST the headlights work.

Pull out the headlight switch and check to see if you have power at- Red wire and Red wire with Blue tracer (with a good fuse in, with key on engine off). If so then turn the parking lights on and you should have power at the Blue wire- If you don't you have a bad headlight switch. Headlights on- power at the Tan wire.

If you cannot turn the park lights on without blowing the fuse (and your sure you have the right size fuse, you have too much amperage in the circuit. In my 91' XJ I have a 15A fuse in the spot for park lamps.

Try removing ALL the parking light bulbs and inspecting the bulb holders... to ensore there is no corrosion on the terminals or bad wiring going to the holder.
While ALL the bulbs are removed install a fuse of the appropriate rating; then turn on the lights with the bulbs removed to see if the fuse blows.... IF it does not... then install one bulb at a time until the fuse blows.
You now have the problem narrowed down to that light bulb holder circuit OR.... there is a problem with that bulb !!!!

Charles

OH this is oh so aggrivating! I had the same problem, where my headlights operated still, but my gauge cluster and tailights didnt work. It became a worsening problem. For a few days everything would work properly, and then not. Today I screwed around with fixing the problem, I checked all grounds, and bulbs, and all were good, and what I thought the proper fuse. However when I would pull the lights on, if I went real slow, the gauge lights and tailights would work, so i figured it couldnt be the fuse. So I replaced the headlight switch. Still didnt work. Finally I checked the correct fuse, and sure enough it was blown. What a waste of time! I learned a nice lesson, double and triple check the obvious! And what you know couldnt be true