Installation of Diode In Roadmaster Brake Light Relay Kit on 2020 Ford F-150

Updated 12/30/2020 | Published 12/28/2020

Question:

I am installing a Roadmaster 88400 brake lite relay kit on a 2020 F150 and I need to install a diode for the brake lite wire. Can you tell me what wires I need to run to the diode?

asked by: Harold P

Helpful Expert Reply:

If you have a Ford or Lincoln that has a neutral tow kit or if your car has a push-button start feature that will not start the engine when the brake fuse is removed, then you need to perform a normally closed installation which involves using a diode-which I believe is the process you're referring to.

I've linked a photo that shows the diode installation when using the Roadmaster Brake Light Relay Kit # RM-88400 that you can refer to, but you will splice into the brown wire on the 4 way that connects to your RV's 4 way plug. You'll install the diode behind a splice in from the brake light relay kit.

I've also linked an installation video of this kit on a similar Ford F-150 that you can use as a guide.

expert reply by: Erik B