Brake light switch/lights help needed
 

Ok Guy's I've searched with no luck. I have a 4l60e trans and upgraded the brake light switch so I can hook up the TCC solenoid. Do I have it wired correctly? Please excuse the drawing as its hard to draw on a phone lol. The orange wire has 12 volts from my American autowire fuse panel. What wire turns on the brake lights? The tail lights only have two wires on them. Running light wire and turn signal. Blinkers and running lights work fine. Please help.

Re: Brake light switch/lights help needed
 

The orange wire is the power wire for the brake lights. The white wire goes to the steering column connector and up to the turn signal switch to power the brake lights.

You'll need to run a key on hot wire to the back terminal on the switch and run your TCC
solenoid wire down to the transmission solenoid.
Do you have a vacuum switch to disconnect the TCC when you are idling in gear?

Re: Brake light switch/lights help needed
 

If it only locks in 4th gear of course you won't need one.

Re: Brake light switch/lights help needed
 

What wire activates the brake lights? The running light wire or blinker wire?

Re: Brake light switch/lights help needed
 

This is for the LS cruise hook up but it also shows the normal hook up as well for the brake switch.
The normal switch has 2 wires connected to it.:chevy:

Re: Brake light switch/lights help needed
 

Thanks for the diagram but I still don't understand what wire goes to the actual brake light.

Re: Brake light switch/lights help needed
 

The wire going out to the back of the truck.

Here is the wiring diagram. Orange wire goes to one side of the stop light switch under the dash at the foot pedal.
White wire goes to turn signal switch in steering column.

Then it goes out as a yellow (DS) and dark green (PS) wire to the back lights for stop lights and blinkers. The brown is running lights.

http://farm4.static.flickr.com/3645/...c2a8064d_o.jpg

Re: Brake light switch/lights help needed
 

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Re: Brake light switch/lights help needed
 

That's how I have it wired up. Everything works except the brake lights. I imagine if it was a ground issue the running lights and Blinkers wouldn't work. Does it matter if I use the lower or upper set of terminals on the switch for the lights?

Re: Brake light switch/lights help needed
 

Have you checked the bulbs to see if they are double elements?

And yes it matter's which terminals you use.:chevy:

Re: Brake light switch/lights help needed
 

I haven't but I bought the complete housing brand new.

Re: Brake light switch/lights help needed
 

Have you checked the harness on the steering column to see if the white wire has power on both sides of it. If it does then you have a problem in your TS switch.
BTW I haven't seen what year truck we are talking about. I sure hope it's not a newer model.

Attachment 1577305


This picture shows the white wire on the end of the plug on the upper side. The lower side wires don't match in colors, but it 's probably a different harness.

Remember you won't have any power on the white wire until you depress the brake pedal. If you have the switch out, the front two terminals should have continuity and power should go to the harness connector.

Re: Brake light switch/lights help needed
 

Truck is a 70. I'll check the harness after work today. I have a flat plug on the steering column and the column is a rebuilt tilt from Kev's classics. I appreciate all your help so far Vettevet.

Re: Brake light switch/lights help needed
 

The flat plug would need an adapter which you must have already since your blinkers work, so the question is "does the white wire have power at the plug ?"

Your brake light wires in the plug should be the yellow and dark green wires. These two wires also carry the power for the turn and hazard filaments in the rear bulbs. If you have power on both sides of the adapter on the white wire, then I suspect that your column switch is not making connection with the yellow and dark green wires in the signal switch.

This is easy to check with a multimeter. Use the DC volts scale and check for 12 volts on the green and yellow wires with the brake switch closed.