Tail light wiring question

[FL71C10]

I replaced the left rear taillight assembly on my 68 c10 because the plug was really bad and the lens was bad, so it was cheaper to replace the whole assembly.

The truck has a bunch of nasty wiring from trailer lights, but all of the rear lights worked except the backup lights (next project). I resoldered the wires back together, and my flashers work but the brake lights dont. Would that be the same wire?

Any suggestions would be appreciated.

Thanks!

[Steeveedee]

It's the same wire at some point. Two possibilities. It could be your turn signal switch, or your brake light switch. To check the brake light switch, put a test light on the two terminals on that switch. One should light. If one doesn't, it's probably the fuse. If you do have power on one side, push down the brake pedal and see if you get power on the other terminal. If you do, that eliminates the brake light switch as the problem. Try that first and let us know what you find. That's two faults to look for, already.