73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Electrical => Topic started by: Chuck Step-a-side on June 03, 2018, 10:04:13 AM
-
I have just installed a LED Third Brake Light below the tailgate and tapped into the lt. green wire for the brake light signal. The Third Brake Light will come on with the parking lights or/and the brakes. Anyone know what can be done to get the Third Brake light to work with the only the brake signal? Thank you.
-
To eliminate circuit backfeeding you will need to establish perfect ground connections to the rear lamps. But, there is a problem with your wiring logic, too.
Light green is backup (reverse), dark green is right turn/brake, yellow is left turn/brake, brown is tail/park/license plate, black is ground. Unless the third brake lamp contains a logic circuit, it will need to draw power from a dedicated brake lamp wire that connects directly to the brake switch, bypassing the factory turn signal switch and rear lamp wiring. Otherwise, it will flash with the corresponding turn lamp.
-
Yes, I was looking at the wiring diagram and saw that I can piggy off the white wire at the brake switch and then run a wire to the + on the third light. Thanks.