Brake light switch
 

I have a question about the brake light switch mounted to the brake pedal assembly. I see the Orange and White wires coming out of the back of it. My question is.....

When the button is depressed, does the switch complete the circuit on the ground side?

If I am correct, does the orange wire go to ground and the white to stop lamps?

I have the wiring diagrams but seem to not be able to follow it with the wires going into the switch assembly.

Re: Brake light switch
 

It's a NC switch. The orange wire comes from the fuse and the white wire goes to the turn signal switch.

All power side switched.

Re: Brake light switch
 

Switch is open when brake pedal is not depressed and button is pushed in.
Closed when pedal depressed and button is out.

Re: Brake light switch
 

the ground for the stop lights is the case of the light bulb to the socket to socket holder to bed to frame to battery

Re: Brake light switch
 

Hmmmm..... So it's on the positive side. Was just curious. I am gathering all the parts and pieces for my OD trans and lock up kit. The TCI lock up kit unlocks when accelerating (vacuum switch) and unlocks when down shifting. However, I want it to also unlock as soon as I apply brakes also.

Re: Brake light switch
 

So when brakes are not depressed....the pedal is up and therefore pushing the button on the brake switch keeping the 12v power from reaching the lights. And when you hit your brakes the pedal goes down releasing the button and therefore applying power to the brake lights. Right???

The following came from the TCI kit instructions:
Option 3 is for those who desire immediate release of the TCC when braking. For
this, you'll need an OEM brake pedal switch with a normally closed circuit. Run
your switched 12-volt source through the brake switch and then to the red wire
on the TCI® external harness.

How can I accomplish this?

Re: Brake light switch
 

I don't know where the red wire on the TCI kit goes.

Two ways I know to accomplish what you want are to install a dual switch. I think the GM N body switch fits and one set of contacts are NO and the other NC. You should be able to find a part number if you search this site.

Otherwise you could use the OE brake switch to trigger a relay that would cut power to the TCC solenoid when the brake pedal is depressed.

Re: Brake light switch
 

The red wire is 12v swithed. A dual switch (one NO and the other NC) would work. The idea is the 12v (red) wire applies power to the 4th gear solenoid. It locks the torque converter when in 4th gear.

A vacuum switch allows the power to the 4th gear solenoid when there is 8-10 feet of vacuum. The vacuum switch unlocks the torque converter via solenoid when accelerating (drop in vacuum). The solenoid unlocks the torque converter when the transmission down shifts.

By placing a Normally Closed (NC) switch in line of the 12v power (red wire), it will allow the capability of braking then accelerating. The torque converter will instantly unlock.

Re: Brake light switch
 

The brake light switch circuit is closed with the switch released. If you push the button on the switch it opens the circuit and the brake lights go off.

"The idea is the 12v (red) wire applies power to the 4th gear solenoid. It locks the torque converter when in 4th gear."

Maybe I don't fully understand but if the above statement is true, the brake light switch will do the opposite action of what you need. When you push down on the brake you want the solenoid to unlock with power not lock, true?

Re: Brake light switch
 

You are tracking correctly. I think I need a switch that does both. One circuit that is open when depressed and one circuit that is closed when the button is depressed.
Attachment 1141617
The brake lights would run through to Normally Closed side and will get power and light up when brakes pressed (button released).
The red 12v switched wire would run through the Normally Open side and the lock up kit (4th gear solenoid) would have power except when brakes pressed (button released)