Hi Everyone, I am working on my Father's 66 Toro. I have no stop lights on the left side but i have stop lights on the right side, i also have turn and tail on both sides. I am stumped because it seems that I should not have stop lights on the right if the left isn't working? maybe i am reading the wiring diagram wrong but it looks like all of the stop lights get power from the same brown wire. Hope to hear from you guys

 

The brown wire is for the tail lights, it is not your problem. The yellow black wire supplies voltage to the lamp for both the brake and directional circuit depending on which position the directional switch is in. I'm going to say you probably have an issue with the directional switch. If the lights are dimmer on the LH side then it may be a ground issue for that light socket.

 

I'm guessing the bulbs were ruled out? I think they should be clear dual filament 1157's

Just re read your post sorry its not the bulbs, turn and stop share the same filament.

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You are.

As noted, the turn and stop light circuits use the same "high wattage" filament in the 1157 bulbs. The tail light circuit uses the low wattage filament. The tail/stop circuits use the same wiring from the turn signal switch to the bulb sockets, so if both turn signals work, ALL of that is good. Your problem must be in the turn signal switch itself, which disconnects the brake light circuit from the lamp and connects the flasher circuit when you use the turn signals. That's the only way you can have the turn signal work but not the brake light. You'll likely need a new turn signal switch.

 

Got it figured out, the turn signal switch is indeed on its way out. It works correctly if you wiggle it. I also had a couple bad sockets and dirty grounds.

is there a write up here on how to change the turn signal switch? Thanks again for the input