Well I went out and put some money on a Chilton repair manual for my 79 F150 4x4. I read the electric schematics and they were pretty easy to read.

Well I wanted to fix my wiring on my rear for my taillights because whoever had the truck before me screwed up real bad. I think they were trying to hook up trailer lights to it.

Anyways, I finally ripped out all of the old trailer wiring hookups and found the wires that were listed in my manual: Green, Brown, Black, Yellow/Blk.

Well on my left tail light they had for the directional was suppose to be light blue/red (I think but I remember it was blue but had another color for stripe) but I didn't see it but there was a Yellow/Blk wire and it says on the schematic that the Blue/Red or whatever stripped wire ran to the Yellow/Blk wire to the directional switch.

But anyways I hooked the wires up and hooked up the Yellow/Blk wire to my left taillight directional wire.

Well I turned on the blinkers and they worked!!! Halllefreakinglujahh!
My running lights worked as well but my stop lights didn't PLUS my left blinker wouldn't flash when I have the running lights on (the left turning bulb on the cluster would get real dim) but my RIGHT one did work with the running lights on!!!!!! I turned off the running lights and the left one started blinking as it suppose to. I could wiggle the turning lever when turning right with the running lights on and it would dimmly blink as I move it up and down.


Well anyways, my fuse blew all of a sudden. I took off my steering wheel and looked for any wires showing but nothing. I put another fuse in and it worked fine then I put my steering wheel back on and I turned on the blinkers again and they worked for a little bit then the fuse blown again..

I HAVE NO FREAKING IDEA WHAT IS GOING ON!!!!!


Any ideas?

 

check your bulbs. mine did this once in awhile. cheap bulbs would rattle and blow. also check the grounds in the tailllights. they are in the same holes as the taillights themselves.

 

But why does my fuses keep blowing like they do when my steering wheel is on yet there is no wire showing?

 

My book shows the left side signal is lt. blue/black to yel/blk on signal switch. The green on the right side goes to the green on signal switch. Solid brown is always your running lights that goes to headlight switch. Back up lights are red/black to reverse switch. Check the grounds good at the rear and the bulbs and sockets. Do the 4 ways work? Switch the four way flasher for the signal flasher just to make sure its not bad. How long has it been since the brake lights didn't work? The brake light switch could be bad.

 

Yeah blue/black...yeah I didn't see that wire back there.

I didn't check my flashers.

I know my front right marker lamp light isn't working, some wires are broken BUT THEY ARE NOT TOUCHING NO METAL.

Brakes haven't worked since I got the truck but before I wired it up we had them working for a bit but they stopped. I have a new brake light switch.

 

Did you adjust the brake light switch when you installed it? If the fuse only blows when the wheel is on, you have a problem in the turn signal switch . It has to be hitting the wheel and grounding out and blowing in the fuse. Ohm the wires from the signal switch to the plug at the bottom of the column. Unplug the connector at the bottom of the column and ohm each wire. This way you will isolate the area of the problem.

 

Yeah I adjusted it all the way and it doesn't close fully. My pedal is still loose where it hooks up to the booster.. will fix that.

 

Here's what I would do - definitley put my short detector in the fuse block at the TS/stop lamp location, and try recreating the problem. If you start buzzing and flashing, then unhook your harness from the lights underneath the dash. If you're still buzzing then its something in the cab shorting out.

What was happening when you blew the fuses? Was the truck driving? The PO may have hacked the wiring and now it shorts to the frame - but only sometimes.

 

Not driving when fuses blown.

 

Make sure the wiring in the turn signal switch is not loose. The steering column is a very cramped space, full of grounded metal, with a lot of wiring snaking around - seating the steering wheel may be just enough to pinch something and short it out.

BLUE with a RED stripe is dash illumination. It's not related to the stop/turn/tail lights in any way. The only reason it goes to the turn signal switch is for the gear indicator on an automatic transmission.

 

I traced a yellow black wire, and that blue wire (which I think it runs to the blinkers?) and found a plug in connector but it's not plugging up to nothing

It the green one to the left

 

That connector is for the factory radio. YELLOW with a BLACK stripe is hot-in-accessory power for the radio, and BLUE with a RED stripe is dash illumination for the radio dial. The original radio grounds through its mounting shafts.

 

Check good in the column. If all looks good, put the steering wheel back on. Put a short detector in as stated and see if you can duplicate the problem. If you detect a short, turn the steering wheel back and forth and see if the short goes away. You can also unplug the harness going to the rear and to the front. You have to isolate where the problem is. Does the flasher even blink or does it just stay on?

 

Ok I just did something the other night...

I put a fuse back in....steering wheel was on, I turned on my left blinker...it worked..then I turned on my right blinker and my fuse blown. Hm...where can I get a short detector?

Also, like I previously mentioned. When I turned on my running lights and turned on my left blinker...it would dim on the gauge and not blink as it should. I could wiggle the lever some and the light would light up some.

So I guess the turning signal piece has had it.

 

Guess I missed what you had said about moving the lever and the lights getting brighter. I think you just found your short. Good luck.