Brake light issue I can't get smart to

[papapavs1]

Hello, '78 K25, and I don't have brake lights anymore. I did a quite a bit of work to the truck, but a few things that may be of interest are: replaced the ignition switch, pulled the bed off for a while to paint it, and had the steering wheel pulled to replace ignition lock cylinder. Went back together and now theres no brake lights. All other lights and signals work. I tested that I had 12v to the brake switch, which I did. Tested continuity on the switch, which I had with the pedal pressed, and opened the circuit with the pedal not pressed. Checked at the block on the firewall, and the green and yellow wires each had 12v on them with the brake applied, down to zero when not applied. But then when I go back to the plug at the back of the box, I get 0v on either wire with the brake applied. I put a signal on, and I get 12v on the corresponding wire, so I know the wires aren't bad. What am I missing here?

 

[PrairieDrifter]

Hello, '78 K25, and I don't have brake lights anymore. I did a quite a bit of work to the truck, but a few things that may be of interest are: replaced the ignition switch, pulled the bed off for a while to paint it, and had the steering wheel pulled to replace ignition lock cylinder. Went back together and now theres no brake lights. All other lights and signals work. I tested that I had 12v to the brake switch, which I did. Tested continuity on the switch, which I had with the pedal pressed, and opened the circuit with the pedal not pressed. Checked at the block on the firewall, and the green and yellow wires each had 12v on them with the brake applied, down to zero when not applied. But then when I go back to the plug at the back of the box, I get 0v on either wire with the brake applied. I put a signal on, and I get 12v on the corresponding wire, so I know the wires aren't bad. What am I missing here?

Are you sure the wires aren't bad? Sounds like a pinched wire.