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I know this is something that has popped up before, but i am not good with electrical so I need a little guidance.
I have a 2004 f150 and the fuse for my stop/turn lamps is blowing only when brake pedal is pressed. I have all front lights working, and reverse lights when fuse is blown. it is just the brake and turning signals/hazards that do not work.
I have replaced the rear stop/turn lamps.
I have looked over all the fuses and they are intact- minus the one
I looked over the wires in the rear and have not seen exposed wires and the trailer lights splicing was done years ago and looks intact and normal. I lost sight of the wires once I got further up the truck.One thing I need to go back to possibly and follow to the front...
I have read that the multifunction switch is a possibility, as is a switch for the brake pedal. that or a short in the wires that I have not seen yet.
I have no experience with a multimeter
any other suggestions based of off this info?
thank you for reading
If you don't know how to use a multimeter, take the truck to someone who does. Your capabilities are going to be limited to either a visual examination or guesswork.
It does not blow when just the turnsignals are used? And both turnsignals(left and right) work and do not blow the fuse?
If the above is the case, then I am thinking it's not going to be the multi-function switch, or the wiring from it to the rear and the rear lights. The rear turns use the same lights and wiring to the rear as the brake lights.
That leaves a problem with the wiring at the brake pedal switch itself, a problem with the third brake light behind the cab, or possibly a problem with the wiring from the switch to a trailer brake controller if you have one, or if there used to be one and now the wires are just hanging around under there.
It could also be the brake wire from the switch that goes up the column to the multi-function switch. The multi-function switch(turnsignal switch) takes the flasher input, and the brake input, and mixes them together depending on if you are just braking, or braking and turning in either direction. It has to do this on any vehicle that does not have rear amber turnsignals. The ones with regular American red taillights use the same filament in the rear for the brake and the turn functions, thus why the complication in the steering column switch.
Brake light switch is a simple contactor never seen one short. The multifunction switch I keep 2 on the shelve cause they go bad often and in all kinds of wierd ways, shorts, no brake lights, hazards not working, thats a common item, but like the guy said in the earlier thread if you dont own a OHM meter, your just throwing parts at it. Have it looked at by a tech.
the truck did have a cap on it with its own brake lamp, my old man took it off before he sold it to me, is it possible something happened to the wiring when he took it off?
Yes, that wire could be hanging around in harms way somewhere. That fits nicely with your symptoms, turnsignals work, brake pedal blows the fuse. The power for that third brakelight circuit comes directly off the brake pedal switch wire. Ford used lightgreen for many years for this circuit.
found the wire that was loose and hanging and unplugged it, now i have my two rear brakes working. but high center is not. hoping its just a bulb replacement, but when i went to check the middle bulb i couldnt pull it out because the bulb is wider than the entrance of the fitting for the lamp socket. anyone else seen this problem? how the hell did they get the bulb in is what im thinking
Some of these outside lights have to be taken completely out of the body to be replaced. I am not sure about your later truck, but I know the roof lights on the early trucks were like this. You had to break the rubber seal and lift the light completely out. Not a good design but what do you do.
Before when the bulb was covered I could not see why the lamp was not fitting through the hole, once i finally got the bulb out, i realized ford designed the lamps to slide in with ease and I noticed the old bulb had been bloated from the short.....
