Topper third brake light

[Reter171]

I have my third brake light connected to the purple and white wire and still have no power to the third brake light. Am I missing a step?

 

[wrench78]

What wires are you connecting to? Taillight wires or trailer wire harness?

 

[jawzs2]

Are you testing with the key on?

 

[Reter171]

Have the red & white topper wire going to the purple and white wire underneath coming off the harness with the two red spares. Yes, testing with key on. No motor running.

 

[wrench78]

are you running a ground wire?

 

[crash68]

Depending on the topper there maybe more than one wire going to the brake light. My Leer topper has two wires that both need to be powered, this is so the brake light can be connected to the trailer light connections and will function like a brake light without flashing when just a turn signal is enabled.
I installed a third brake light just above the license plate and have it wired using the pur/what wire, be sure the light your wiring has a good ground and proper polarity (don't rely on wire color).

 

[Reter171]

Ran a test on the light, light works with just power and ground. Been reading and it says to hook up to the purple and white which is how it was hooked up when I bought the truck but still does not work

 

[Reter171]

It is grounded to the frame from the previous owner

 

[wrench78]

Ran a test on the light, light works with just power and ground. Been reading and it says to hook up to the purple and white which is how it was hooked up when I bought the truck but still does not work

This would leave me to believe that it's an issue with the cap light, not your wiring. Only thing that comes to mind, would be is the cap lights LED? if so, maybe try switching the wires around. Maybe your hot/ground wires are reversed in the light.

 

[Reter171]

I will try to switch them and post my results later

 

[wrench78]

I will try to switch them and post my results later

Any luck?