electrical problem I'm stumped
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From: SW Missouri
electrical problem I'm stumped
1976 F-series.
the brakelights dont work, neither do the front turn signals, or hazards. I thought it was the wiring in the steering column, but after swapping columns, there was no difference. there is no power to the brake light switch, and if I jump power to the brake light plug, it shorts out.
all running lights work. headlights work, everything else works. turn signal indicators work, with the rear turn signals.
any Ideas?
the brakelights dont work, neither do the front turn signals, or hazards. I thought it was the wiring in the steering column, but after swapping columns, there was no difference. there is no power to the brake light switch, and if I jump power to the brake light plug, it shorts out.
all running lights work. headlights work, everything else works. turn signal indicators work, with the rear turn signals.
any Ideas?
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Joined: Jul 2003
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From: okc
that happened to my F-250, same lights and all...tried wiring up the brakes like you said and it burnt the brake wire completly through the wiring harness, it was quite the mess, turned out my wiring harness running to the rear of the truck fell on the muffler and melted all the wires, melting the brake wire to the side of the muffler, which explained why it shorted out on me.....id check all the wiring coming out of the cab...........
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From: SW Missouri
yeah I looked there, he had a diffeent issue. I'm going to find the wiring schematic today...
then I get the joy of replacing the heater core in a truck that has been converted to factory air... ugh...
rear signals work, so I know the rear wiring is ok, the parking lights all around work, and the headlights work, but the front signals and hazards dont. I thought that the turn signal switch seperated the front and rear signals, so the brake lights will work.
so my plan is to trace the source of power to the brakelight switch, and front flashers.(and hazards)
then I get the joy of replacing the heater core in a truck that has been converted to factory air... ugh...
rear signals work, so I know the rear wiring is ok, the parking lights all around work, and the headlights work, but the front signals and hazards dont. I thought that the turn signal switch seperated the front and rear signals, so the brake lights will work.
so my plan is to trace the source of power to the brakelight switch, and front flashers.(and hazards)
Last edited by whd507; Dec 17, 2004 at 08:57 AM.
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From: Northern Illinois
Originally Posted by 76Forder
did you check the lil flasher fusebulb thing? or 76 didnt have em did they?
whd, is it the brake lights that don't work as stated or is it the rear turn signals that don't work? Or is it both.
If they are not lighting up at all it will not be the flasher, I presume you have checked the fuses and bulb's?
and if I jump power to the brake light plug, it shorts out.
turn signal indicators work, with the rear turn signals.
Never mind, just read your second post, check your harness at the firewall. Might be a bad connection there.
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From: SW Missouri
I changed the steering column, to a tilt unit I had lying around,, and that allowed the front signals to work, as well as the hazards. all the turn signals worked, until I tried the brakes, then the right rear signal acted up, and the brakes worked very dim. the switch got hot, so its to the very rear harness next. the harness from the firewall to the rear bumper checks out ok . the rear signal worked fine yesterday, and today before I tried the brakes.
but at least there is progress...
but at least there is progress...
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From: Wilton, Ca
It sounds to me that the trouble is in the brake switch. Your turn signal and brake are the element in the bulb,So if the turn is working at all means you are getting current to the rear.With a test light I would check the brake switch.You probley know this,But in case one side is hot and the other is hot when the brake is deprested.If this checks out then it has to be a groung.A bad ground will cause it to be dim and work off an on. If the splices are a mess once you have the problem solved you should solder the splices.I have had a lot of trouble with wire conectors (corrosion)If you have them that could be some of your trouble also
I hope this helps. I had a lot of trouble with the brake lights on my 5th wheel,So I know what you are going through
Don
I hope this helps. I had a lot of trouble with the brake lights on my 5th wheel,So I know what you are going through
Don
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From: SW Missouri
I found it, it was a bad trailer wiring connector. when the previous owner added a 4-pin connector, he wrapped it around the rear corssmember, and wedged it against the tank edge. both the green and yellow wires were bared. I guess it wasnt enough of a short to affect each individual turn signal, but when the brakes were applied, it was too much, (?) but when I repaired the areas wiring, and added a 7-pin combo plug, the front signals, hazards and the brakes work. (!!??!!)
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From: okc
sounds similar to what i was saying above, only without melting on the muffler....glad you worked it out and got lights again....its always refreshing to know someone conquered a Ford truck wiring puzzle....