Getting brake lights to work

[RustyPile]

Originally Posted by waters5

The truck has a new American autowire harness installed with LS3 motor and all new LED lights. I have tested the brake switch with continuity to verify it’s functioning. When I unplug the column turn signal wiring lights go to normal. When I swapped to a new turn signal switch the lights behave the same.

When I unplug the brake switch verified I have hot power on orange wire and no power on white. With ignition on the white wire on the brake switch connector shows a dim light on tester.

When I test the rear body harness wiring mentioned in the thread previous tips everything tested fine.

Headlight switch off with ignition on: brake lights and blinkers work normal
Headlights switch on: brake lights work normal
Headlights and ignition on: only blinkers work and lights are on as if brakes are engaged.

http://http://https//api.americanautowire.com/shopify/instructions/92970223%20510347%20IN%202.0.pdf

That is the messiest wiring diagram I've ever seen..

Have you checked both sides of the T/S plug for correct wire position?? What were the results when you removed all those LEDs and put the incandescent bulbs back in???

Have you checked to see if some random wire is erroneously connected to something else, or not connected at all?? The clue to this is the brake lights being on with the ignition switch and headlight switch being ON... These 2 circuits are 2 entirely separate and different circuits, NOTHING is shared... NOTHING connected to the headlight switch is also connected to the brake lights nor turn signal lights.