Hookin up the brake light on a pick bed cap.?

Question

Hey, I recently bought a bed cap for my pick up and need to know how to hook up the brake light on the bed cap so that when i step on the brakes the light on the cap goes on as well. Now the bed cap as two wires, im planning on running them straight to the rear tail light but not sure which of the two wires from the bed cap connects to which of the wires on the tail light, can anyone help me with this? thanks...

Answer 1

Most likely, your PU bed cap is fiberglass - hence, insulated with no direct connection to ground. Therefore, one of the wires should be connected to the hot lead from the brake light, and the other goes to ground.

If your bed cap brake light is a regular incandescent lamp, then it won't make any difference which wire is hot or ground. (The usual convention in the US, if you want to follow it, is the body of the bulb is ground and the button is hot. So the wire which goes to the connector body would be ground.)

If your bed cap brake light is an LED type, then polarity is important . The cathode is tied to ground, while the anode is tied to hot. You can check which wire is which with a jumper from your truck's battery: the LEDs will illuminate in only one direction of wiring.

Make sure you connect the hot wire from your truck's brake light - not the left or right turn signal light, and neither to the tailight that comes on with headlights. Each truck's wiring will be different, so use a voltmeter to find the correct wire.

Good luck.

Answer 2

These wires would hook up exactly the same way. There isn't a way to reverse them.

I did a similar thing on my truck when I got a roll pan. The pan wouldn't accommodate the original license plates lights so I got the lights that people use on their windshield washers (the cool LED ones). I then used the bare wires that went to the old lights to connect the new ones.

Answer 3

First off, pop the lense or pull out the house on the light on the bed cap, check it to see which wire hooks to the light and which one hooks to the housing (aka ground).

then get a test light, pop the rear taillight lense out of the truck, and figure out which wire you hafta tap into to get the brake light.

use good wire connectors and maybe some di-electric grease and have fun.....