Been having this nagging issue with My '59: I have right side brake light only, but I have both left and right taillights.. Both bulbs are new. What could the issue be? I have brand new stoplight switch installed

 

It might be a dirty turn signal switch! Brake lights run through the turn signal switch. The turn switch opens or closes the circuit to each rear bulb. If these contacts are dirty that circuit won't open. You can try to blindly squirt contact cleaner in the switch, but it is best to remove steering wheel and access to switch to carefully clean the contacts. Before doing that I would confirm the current stops at the switch. You didn't say if your blinkers are working front and rear both sides.

 

Blinkers working front and rear, right side only. Brake light right side only, Tail lights both sides

 

Because both front and rear left blinkers are not working, my money is on the blinker switch!

disclaimer-----I'm not always correct!

 

Damn, I have to find a way to bypass the thing, to get My left brake light to work

 

Remove the bulbs from the sockets, use a pencil eraser to clean the contacts of the sockets, which are prolly corroded.

 

I ran a jumper wire from the right side light,and got the left brake light to work.

 

Jeff; Because the brakes and the blinkers share the same filament in the bulb, the rear blinkers will now both blink at the same time. Why not just clean the switch?

 

You have just converted your turn signals into Emergency Flashers! LOL

 

This is not occurring, only right blinker works as before

Also,because I'm tired of tearing things apart, gonna just enjoy and DRIVE it awhile. Main goal for now was the brake light

Ummmmmmmmmmmm NOPE, Only the right side turn signal is working as before, running the jumper did not do anything other than getting left brake light to work

 

Do your brake lights work with headlights on?

 

Yes they do

 

Awesome! I'd like to see that wiring diagram!
Glad you got it figured out.

 

What diagram? I just took a shot in the dark