Where Does Roadmaster Brake Lite Relay # RM-88400 Install

Updated 04/09/2019 | Published 04/08/2019

Question:

Where is RM-88400 installed?

asked by: Barrry W

Expert Reply:

I attached a diagram that shows where all of the connections of the Brake Lite Relay part # RM-88400 need to be made. Basically the 85 pin gets grounded, 87 gets ran to brake light switch and signal output, 86 runs to a fuse tap, and 30 runs to the brake light wire.

I also attached an install video for this kit for you to check out as well.

Here's an instructions overview for more info.

Remove the blue wire from the kit. This wire is not needed for normally open applications.
Locate the brake-light-switch wire in your towed car.
Remove the brake light fuse.
Cut the brake light wire a few inches away from the "cold" side of the brake light switch.
Attach the relay to the wiring for the RV braking monitor. The diagram above shows where the green wire attaches the relay to either a Roadmaster Even Brake or BrakeMaster system.
Connect the black wire of the relay to the brake light wire near the brake light itself using the included blue butt connector.
Identify a fuse that is only powered when the ignition is in the "run" position and not when it is in the "tow" position. Pull the fuse. Insert the fuse into the slot closest to the fuse blades, then insert the fuse tap into the empty slot in the fuse panel.
Using the attached blue butt connector, connect the red wire from the brake relay to the wire from the fuse tap.
Ground the white wire to your towed vehicle's frame.
Secure the relay with the included wire ties.