I am still going nuts over this problem.

My brake lights and four ways do not work at all but my front turn signals do, all other lights work just fine.

In place of the fuse for the brake flasher was something marked tung-sol 20a 12v on one side and made in usa 163 on the other. I will post a pic if I can.

This thing was almost too hot to touch when I pulled it out. I cleaned up the wiring at the back of the truck and everything looks ok. I followed the bundle to the front and it looks fine. I can't see above the gas tank though. I put jump wire accross the fuse and the tabs that hold the fuse in turned cherry red in about 3 seconds. I can find no loose/frayed wires or connections could the flasher for the 4-ways cause this. I don,t think it is in the turn signals because the front ones work.

The pciture is in my album I can't figure out how to get on here.

I have the wiring diagrams but the more I stare at them the more confused I get.

Thanks

 

Well, the brake lights and the turn signals go through the turn signal switch. So, apparently it's AFTER the turn signal switch itself(or the front lights would have issues).

Does it short out without having anything connected? Or only when you activate the brake/turn signals?



That would be a circuit breaker. It resets automatically after cooling down, so you dont have to keep replacing a fuse. I'm guessing the PO put that in so he could at least use the truck without replacing fuses constantly. Not a good fix.

 

Yes it does short out with nothing turned on. As soon as I jumped the fuse holder it turned bright red. Seems like it has got to be a dead short in either the brake or 4-way circuits. But I can't find anything. Could the flasher cause this?

 

Shouldn't. It just takes current draw and turns itself on/off. Basically a bimetal strip that moves. Unplug it and see.

So, at any time it is short circuited. Hmmm, time to start unplugging things and see what eliminates the short. Unplug the turn signal switch at the bottom of the column. Anything better?

Then unplug your brake light switch. Anything??

4 way switch??? Anything?

 

Thanks again, I have to get my daughter from school in a few minutes, but I will start with ideas as soon as I can.

 

Disconnected brake light switch still shorted, the 4-way switch looks to be hardwired in but taking out the flasher should cut power to it still shorted. There are so many splices and extra wires under the dash that I couldn't find the plug for the turn signal switch. If I am reading the wiring diagram right everything goes through the turn signal switch last thing before going to the back of the truck. Is this right?

If it is then it has to be one of those 3 switches because any short past them wouldn't show it self unless one of those switches is closed. The short is there without any of those switches being closed.

Thanks again.

 

The turn signal plug should be right at the bottom of the column, with the wires coming out of the top side of the column. Like 6-8 wires in a group.

I'm not really sure of the proper wiring of everything, and don't have a good diagram in front of me. I would guess the T/S switch is the last place before going to the rear of the truck. That would be the place the determine if they blink or stay on.

I would assume that there is one hot wire in the T/S switch, as it would need power to flash the rear lights without having the brake pedal pushed. This would be a place to look to find the short. That is where unplugging the harness at the bottom of the column would isolate the T/S switch itself(or at least the wiring going up the column).

 

I think I am narrowing it down on the diagram plug "f" the wire coming from the turn signal switch have been cut and some sort of relay? was put in I put a picture in my album but can't figure out how to get it into the thread.

Any how I did not unplug the turn signal switch because everything looks really fragile with lots of extra splices in the mess. I think I am going to try LMC for a new connector and rewire that setup per the diagram. the mess of wires was ziptied together when I cut the ziptie I found some bare wires and some shaky connections. I still need to track some of these wires.