How to Wire Triple Tail Light with Separate Stop, Turn and Tail Light Functions

Question:

Led lights have red black and white. My Grote 3 stud box has a dual filament bulb one filament is running light the other is brighter for brake and turn lift. I am installing 3 led lights 2 red 1 clear for reverse. Reverse is easy. Can I connect the two reds so both are on for running lights? Also I want one red for turn and the other red for brake.

asked by: Steve R

Expert Reply:

If what you're trying to do is replace your Grote incandescent tail lights (very similar to the Optronics Jeep-Style Tail Light # ST60RB) with three separate LED lights, or a Triple Tail Light, like # 47-85-002, then connecting the two black wires on the red LED lights is what you want to do for running lights.

Most modern LED lights that have a 3-wire pigtail, use the following color functions:

Red: Turn signal and brake
Black: Tail light
White: Ground

If you haven't already done so, use a circuit tester, like # PTW2992 to test the wires that were previously connected to your incandescent light to determine which controls the turn signal circuit and which controls the brake light circuit. You can then connect one red light to each using the red wires on the lights.

Since your previous lights grounded through studs, the easiest way to ground your new lights is to combine all ground wires and use a heat shrink ring terminal # DW05740-1 and self tapping screw # FA1131822 to attach to a clean, bare metal surface on your trailer.