Turn Signal Electrical Problem... HELP!!!

[GosaGT1988]

Okay, here we go. My front turn signals work fine but my problem lies in the tail end. If I use my right turn signal, my emergency flashers on the rear end start flashing, if I use my left turn signal, nothing happens. My voltage gauge in my dash reads low, my headlights are dim, also my brake lights do not work whatsoever. What could be the problem???

[48wilys]

Bad Ground? Dead Short?

[Wildman]

Yea, sounds like a bad ground.

 

Pull the left (driver's) side tail light and check the body ground.

 

Also check the connector at the rear left side, about 6 inches in from the bumper, clean and use die-elect grease in the connection.

 

Those are the easy, first step to the repair.

 

Also pull the lights out, clean all the sockets with contact cleaner, and coat the sockets with die-elect grease. Make sure you install the bulbs correctly, and check the bulbs that the filaments are good, or replace the bulbs.

[GosaGT1988]

I got underneath the truck and it looks like the harness for the tail lights is still there but someone has rigged up a black wire that runs from the front of the truck (possibly into the turn signal lever) all the way to the harness itself. I'll check everything else but would it be a good idea to have an electrical shop take a peak if the bulbs and whatnot are not the problem? Or can someone tell me how to A.) Find the proper replacement harness because the one there looks to be in real rough shape and B.) Properly install a new harness or repair the wiring on the existing one.

[Wildman]

Oh Boy....good guest what some one else did, running that black wire :dunno:

 

Best to get a test light on it first to see what it does, or if some one added a ground wire.

 

The OME harness has crimps in the line to part off the different lights, I've found that, and best to take the crimps out, use B-caps with die-electric grease packed in them for a replacement.

 

I could dig thru the parts shelf and I think I have a '87 harness some place.

 

But I would fix your first, would be easier, and you'll know what you'll have too when your done ;)

 

It's a little time consuming, so going to a electrical shop could run up some$$$$ :eek:

[GosaGT1988]

Okay, I finally got some time to work on the electrical problems. I checked out that black cable, it went into the firewall but was connected to absolutely nothing on the opposite end. There was a grey wire with a black stripe at the taillight harness that was cut so I reconnected those. Brake lights still don't work, emergency flashers stopped working, left turn signal still doesn't work but whenever I use my right turn signal the emergency flasher does not go off which is one problem fixed. Now my instrument panel light fuse keeps blowing. I replaced every single one of the bulbs today, new headlights and boy what a difference it all made. I was so frustrated at the electrical problem I went ahead a repainted my grill and the trim pieces for the headlights and everything black, I'll post some pictures later. Anyways, I just can't seem to figure out the problem. I'm doing everything I can to avoid an electrical shop. Please help! :dunno:

[ifixit8]

have you checked the fuses? I found out that on my fuse box some of the terminals are very loose, I had to shove some metal in with the fuses for them to make contact. another thing that you can do is get a haynes manual and trace what each wire does, along with a multimeter and figure out if your getting the correct voltage at the right wires. I had to remove trailer wires and replace my license plate sockets awhile back. having that book helped alot. hope that helps.

[Wildman]

I checked out that black cable, it went into the firewall but was connected to absolutely nothing on the opposite end.

 

Figured that much, like I said, you don't know what some else did to the wiring :roll:

 

There was a grey wire with a black stripe at the taillight harness that was cut so I reconnected those.

 

Thats your left turn single wire.

 

I've attached the wiring diagram for the rear lights, should help you out.

 

When you replaced all the bulbs, did you check the sockets too, were they corroded, or have any "green" on the terminals?? thats a show sign that there a problem with the socket.

 

You should take each circuit and trace it down, one at a time, like get the brake lights working first, then the turn signals......and so on, this will create less of a mess, than just replacing everything.

 

In the start, you said your front lights were working correct, just problems with the rear lights?? Now your blowing fuses in the dash lights?? That could be the start of the light switch going/being bad, or the turn single switch having a short in the steering column. Lets get the rear lights fixed first, and then back up to the dash light.

 

[GosaGT1988]

Took the voltmeter to the rear lighting harness and there's a good possibility that's where my short is. Quite possibly need to replace the harness itself. Have to look around and see if I can find one, preferably new.

[GosaGT1988]

Alright, update. I got the rear left and right turn signals working. Emergency flashers on the rear work as well as the rear running lights. Instrument cluster lights are working again. I still don't have reverse lights or brake lights. I check the brake light switch and that has voltage. I still need to check the reverse light switch but don't know where it is. My front turn signals don't work at all however. Headlights work and front running lights work fine.

[Wildman]

Your back up lights come off the NSS (Gear Selector Switch), that shows on the digram I posted.

 

The brake lights feed thru the turn signal switch, that's why I'm thinking you might have a problem in there??

 

For your front turns, do you have the correct bulbs installed?? In the correct position??

 

Like I said in the beginning, it's going to take time to track down the problem, the good news is your not paying a electrical shop $75 hour to track down the problem ;)

 

Your other post wrote you needed a new rear harness, yea, if you can find one??? If you have not, start pulling it apart and look for the metal crimps, and check them out / replace them.

 

Still waiting to hear what shape your sockets are in????

[GosaGT1988]

Sorry about that, they are in good shape. I went ahead and sprayed them clean, greased them up and put the bulbs in. The front turn signals did work at first but as soon as we solved some of the problems with the rear lights, they stopped working. Yes it has taken some time but it's a whole lot cheaper. The previous owner put a steering column from an '85 XJ in there. I found one in the local car yard from a '90 XJ which will have the exact same color codes and everything for $50.00. The way it's looking right now, the problem is very possibly the turn signal switch. I'll definitely keep you updated.

[Wildman]

Wait a minuet.

 

The steering column is from a '85????

 

And your MJ is a '90????

 

And your wondering why your lights don't work?????

 

:shake:

 

Would have been nice to know that detail up front ya know :roll:

 

Ah, Yea.........I think you better change out the column with the right year, and then fix all the splice up wires that made the '85 work "some how"

 

And get the right year turn single unit in there.

 

That would solve 3/4 of your problems.

[GosaGT1988]

I did not know that until this afternoon when I got up under there to test the brake light switch. That's when I decided to go see if I could find a steering column from a '90 MJ or '90 XJ. No luck on the MJ but found two '90 XJs. By the way, what would it take to add cruise control to my MJ?