How to wire 3rd brake light??

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gdizzle

gdizzle

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in my 66 dart, it has rear tail lights that have the 2 elements in it, one for stop, one for blink.there are 2 wires feeding that lamp socket.

I am having trouble hooking up a 3rd brake light to the wiring. I thought it should just be as simple as figure out which wire (there are 2) is the stop light, tap it, then run it to the new brake light which has 2 wires. I thought I then ground one of those new wires to the body and it should work? But not working. what am doing wrong?
 
You're on the right track. Pick a brake/turn signal wire as your feed to tap in to like you did. Now wire in the and/or gate , unless the 3rd light has one already pre-wired, (don't know the third brake light term for it) and you should be good to go. One wire into the 3rd light and the other coming out to ground..... make sure the bulb in the 3rd light is good.
 
The easy way is to tap into the wire before it goes to the turn signal switch right off the brake light switch, it's a longer wire but a lot less hassle and no diodes.
 
The two elements are not for stop, and blink. One is stop/blink, (bright) the other is taillight (not as bright).
Either of the brake light wires is also going to be a turn signal wire.
The gate he is referring to will use the signal that is on steady to operate the third brake light, regardless if one side is in turn signal operation.
Much easier to do as Brian suggests.
 
A lot of the 3rd brake light kits came with a logic circuit that would prevent blinking with turn. It was wired to both left and right / green and yellow. In my experience those little boxes didn't live very long ( replaced every few years ).
There is a better way. Find and tap into the white wire between the brake pedal activated switch and turn signal switch. Buy about 25 feet of white wire and route it in with the rear light harness along the left side of the cabin. It's important that this is done properly since a short at a sharp will blow that fuse, thus no brake lights at all. Do it right or don't do it at all.
 
Ok I ran a wire from the switch. There was no white wire. There was yellow or pink. I guessed at which one to tap into, the yellow one. This is the one that sits stationary on the switch. The other wire sits on the plunger part of the switch and moves in/out when pedal goes down.
It works, but did I tap into the right wire/side of the switch?
 
gdizzle said:
Ok I ran a wire from the switch. There was no white wire. There was yellow or pink. I guessed at which one to tap into, the yellow one. This is the one that sits stationary on the switch. The other wire sits on the plunger part of the switch and moves in/out when pedal goes down.
It works, but did I tap into the right wire/side of the switch?
Click to expand...
Either side is fine at the switch
 
moparmat2000 said:
Either side is fine at the switch
Click to expand...

No! 1 side comes from the fuse so the light would be on all the time.
The other goes to the turn signal switch, so if it works with the pedal it's right. Good job.
 
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