The Stovebolt Site Forums The Shop Area The Electrical Bay Help me wire my tail lights.....don't make me beg

Patient: 1958 Apache short bed side step.

Problem: Driving lights come on, turn signals work, when driving lights are NOT on brake lights work...when lights are ON brake lights don't do anything.

Here is what I did: Had a pair of crappy iron cross tail lights on the truck when I bought it. I took them off and modified stock tail lights to add another two wire socket and bulb...because that is how the after market units were wired....except they had a single wire socket for the second bulb (the second bulb was the flasher/turn signal bulb and it grounded to the housing.

So, I "cleverly" wired the main bulb as it had been, then wired the third wire sticking out of the back of the truck, the "flasher wire," to the new two wire socket and the other wire (which I presumed to go to a ground) I connected to the same ground wire as the main bulb.

OK, what did I do wrong?

just what you said, wired 2 sockets together - the way the rear lights work is the 2 wire bulb is taillites [same as front parklites] on one wire, brake and turn both on the other wire, when signal is on it uses the brake filament, brake light gets power thru the signal wiring ... the extra socket is excess, wire the dual filamet socket up according to the shop manual wiring diagram and ignore the other

Bill

OK, so disconnect the second socket I added from the "ground" wire I thought I was connecting to, and instead run that wire from the additional socket to a sheetmetal screw to ground it....will that work?

the ground is via the case of the socket and the body of the light, no "ground wires" on anything, just make sure the body of the light is well attached to the truck, which is the ground - sounds like what you done is set things up so under some conditions, the power to the bulb is being shorted to ground :confused:

Bill

Thanks Bill,

Some day I'm going to learn the black art of automotive electircal wiring.

It sounds to me like the truck has an aftermarket turn signal switch which requires it's own, second set of bulbs. I can think of no other reason for three wires to a side.

Yes, the truck has an aftermarrket turnsignal unit strapped to the steering wheel shaft. Sorry I didn't make that clear. Looks like a formere owner hacked into the wiring harnes to add it, and also it has a roll pan with two lights for the license plate.