How would I hook up a 3rd brake light to work in tandem with the stock ones? I found one that fits perfect while at the junkyard and would like to add it.
Third brake lights are controlled by a circuit call an "AND" gate. It is a simple logic circuit that needs input from two sources before it will light the third brake light. Some lights have them built into the lamp assembly and others use a discrete circuit boad.
Ive always ran the wires directly to the driver or passenger side lights with no problem...find which wire goes to your brake light(not your parking light) and hook it up to that one. It doesnt dim the bulb you run the other off of, if it did I didnt see any noticeable difference. NOTE: Jamie reminded me cars who does not have amber turn signal lights cannot be wired this way...lol
Your brake light switch is at the base of your steering column. One side is always hot and the other side is the switched side. Tap it into the switched side.
If you do this, the third brake light will flash when you turn on the turn signal of which ever side you wire it too.
Ohhh yeah...I forgot about that...I did this to my prelude...which had the amber light...whoops... Scratch what I said...lol
I pulled it out of a little hatchback. Been too long for me to remember what it was. It fits up against the back glass perfect, though. I will certainly take pictures.
