Topper 3rd brake light on a 2015 tacoma

I just bought a used Lear topper and am trying to wire up the third brake light. I went to the local topper dealer and he said I had to run a wire from the brake light switch since I have LED brake and tail lights. Something sounds fishy here, I have the trailer towing option on the truck so shouldn't there be someplace to splice on that wire harness or a plug in connector to make this 3rd light switch workable?
Thanks in advance.

 

I have an LED brake light in my Ranch topper, and it's just spliced into the left tail light wiring. Should be simple...

 

I hooked it up to the correct wire (green with red stripe) and ground but it doesn't work. It will however work when I plug it into my trailer hitch lighting socket.

 

What color wire did you use for ground? Or did you just ground the negative? I just hooked mine up yesterday and I used the green with a red stripe and the white with a black stripe for ground. Also remember with led polarity matters so if it doesn't work you may need to swap your connections.

 

I just grounded it to a bolt, I'll try this, thanks

 

http://www.tacomaworld.com/forum/te...ll-wiring-step-step-picture-load-warning.html

Try this thread by majorhavok it might help. Did mine months ago it work. Buy the 3rd brake light leer connector for easy removable or permanent type of wiring.

 

Thanks NAZLAX10, this worked like a champ!

 

Glad it worked for you!