How To Help with 12/1973 FJ 40 brake light wiring please

[Toby755]

1. New to wiring. Bench testing a 12/73 40 series wiring harness. Having trouble with my brake switch, which is NEW OEM. When I depress the switch, the tail lights go out. Pics as shown. I have 12 volts to the Green/Red wire at the brake switch. No power at the Green White wire when the switch is not plugged in but continuous power at the green white switch when the switch is plugged in. When the switch is depressed I have no power at the Green/White wire and the power goes out at green/white to the tail lights. Any ideas why?

2. The red/white wires at the brake switch have no power at any time. Aren't they supposed to have power when the emergency brake switch is pressed so the warning light goes on on the dashboard. Also, there is a long red white wire that goes into the engine bay, seen coiled in 3rd pic. What does this go to?

3 Anything I need to do to delete the computer and VSV other than unplug them?

Thank You!

 

[B y r o n]

Don't have documentation in front of me but remembering that the brake circuit also includes your handbrake switch as well as emergency flasher wiring. Troubleshooting will involve all three areas as well as grounding points for these circuits.

 

[charliemeyer007]

When you depress the brake pedal switch the brake lights at the rear should go out - that is what happens when your foot is not on the brake pedal - the switch is depressed.

On my 72 the e-brake switch would light up the red brake light on the dash, the two sensors on the brake master would also light the red brake on the dash.