Hot Rods tail light woes

The rear turn signals on both sides of my truck work but I can't get the brake lights or tail lights to work. They used to work but stopped working. Any thoughts? The head lights work and the front turn signals work. Thanks for any help.

 

It has to be something common to the brake and tail lights. Probably their ground. Can you pull the tail light bulb and measure voltage there? Can you measure 0 resistance from the bulb housing to ground? Can you find a wiring diagram for the truck?

 

If your turn signals are separate lamps from your brake lights, then it's probably a bad ground at the lamp sockets as noted. If the brakes/turns share a lamp on each side, then you have two separate problems. The taillights will probably be a bad fuse, poor socket connections, or failed headlight switch. The brake lights will be one or a combination of no power in the circuit, a failed brake light switch, or a failed turn signal switch.

 

First step on a truck is to slide under the back end and see what kind of rats nest of trailer wiring some previous owner (s) have stuck under it. All too often those scabbed on wire it up so we can tow a trailer hookups are the problem with the stop and tail lights.
Other than that.
If the turn signals have a separate bulb you are dealing with the stop/turn bulb.
I can't find a wiring diagram but am thinking that the stop/tail lights might run off the same fuse in the fuse block.
Other than that connections where there are plugs built into the wiring to unplug the bed lights from the harness that runs though the chassis. I think the stock wiring had one at or around the back or next to back crossmember.

A good test light is your best friend on this as you can check the flow of power front to rear to see where the issue is.

 

I'm going to guess you have a task force truck based on your avatar. Mine had the wiring from the original turn signal going down the inside the steering column chewed. When I would hit a bump or move the truck a certain way the turn signals and brake lights would stop working. Hit another bump or make a sharp turn and they worked again. Might be worth a look if you have an original turn signal. I wrote a tech on reconditioning them D2-53 guide.

 

There are two circuit breakers built into the headlight switch, one powers the brake lights and tail lights, the other powers the headlights.Turn signals get power from the ignition switch.

At least that's my guess what's wrong, assuming it's a stock wired 55-59 chevy pickup

 

Like to hear the outcome of this. BigStar, please let us know what it was.
I trust you'll find it presently.

 

What of turn signal switch are you using. 7 Wire or 4 wire. 7 wire runs brake lites thru the T/S switch. That is where your problem probably is. Good Luck

 

Thanks a lot guys. You don't want to see what the wiring looks like The truck has an aftermarket fuse box and wiring that the previous owner installed. The brake/turn signals work off the same bulb. The tail lights and brake lights did work but now don't. I will take some of your recommendations and check a few things and let you know what I find out. Thank you

 

First see if power is getting to the brake switch and light switch.

 

Have you checked the brake light switch? HRP

 

My first thought would be a bad ground but with both sides acting up that would be unusual, for that to be the case it would mean a bad ground between the bed and the frame. Yeah, a test light would be your friend here, most guys start at the light and work forward, myself I start at the fuse panel and go from there. For it to be just brake and taillights the 2 circuits must have the same power source (fuse). I'd start at the brake light switch, follow it back and see where it gets power from, I'll bet it's from the taillight circuit. If it is, you lost power before the headlight switch but after the fuse panel, assuming of course you did check the fuse and if the fuse has power to it.

 

Is it mechanical or a pressure switch ? HRP

 

Why guess, or ask the internet to guess? Get yourself a circuit tester, or voltmeter, and trace out the wiring. It's the only way to be sure, and you'll learn a thing or two about wiring and electricity as you work on it.

 

Check the bulb sockets, could be old and corroded.

 

98% of the time,,,
Goofy electrical stuff is tracked down to be a bad ground.

Only one of The bright sides is working at a time and only thru the flashers
+
The low side is in op and the high side is in op on its own when independent of the turn signal switch of flasher.

Well that = goofy electrical stuff.

 

First off, you need to be specific as to whether or not the brake and turn signals are using one bulb filament. If so, then turn signal switch, and or brake switch is either bad or not getting power. Tail light not working is probably fuse burned out.
If turn signals are separate, then brake switch and it's power needs to be checked for brake light issues. Tail light not work too looks to be bad ground, but usually bad ground allows either brake or tail to work, but not correctly.

 

The first thing I always do with tail light or brake light problems is replace the bulbs. Next step is check sockets and grounds. Fixed several problems with new bulbs.

Gary