Will Third Brake Light of Towed Vehicle Illuminate When RV Brake Apply with 4 Diode Lighting

Question:

I am rigging my 2001 Jeep Wrangler Sport to pull behind my Thor motor home. I have installed a 4 diode system to control the lights, and a Blue Ox Patriot BLU37TR supplemental braking system. The Blue Ox seems to work great. But, the third break light above the spare tire will not light up when I brake from the motor home. It works fine when I apply the brakes from the Jeep, but not from the MH. Have I done something wrong, or is that a normal situation?

asked by: Bob R

Expert Reply:

You did everything correctly. The 4-diode systems do not tap into the third brake light circuits so they will not activate when the Blue Ox Patriot # BLU37TR applies the brakes.

expert reply by: Jameson C