Installing The Roadmaster Brake-Lite Relay Kit On A 2016 Ram 1500

Updated 03/07/2022 | Published 03/03/2022

Question:

Im in stay a universal brake light switch and the instructions say to hook the blue wire to the supplemental braking system. I dont understand where to hook it and which wire to hook it to. I also what is meant by the monitor input.l

asked by: Stanton E

Expert Reply:

Before installing the Roadmaster Brake-Lite Relay Kit for Towed Vehicles # RM-88400 you need to determine if your 2016 Ram 1500's system is normally open or normally closed. 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.

If your Ram is a normally open system you'll complete the following steps:

1. Remove the blue wire from the kit. This wire is not needed for normally open applications. You can just cut off and cap this wire off with some electrical tape.

2. Locate the brake-light-switch wire in your towed car. This wire will be towards the top of your brake pedal and may require you remove some of your dash to gain access to it.

3. Remove the brake light fuse.

4. Cut the brake light wire a few inches away from the "cold" side of the brake light switch. The cold side of the switch is only going to have power when the brake pedal is depressed.

5. Attach the relay to the wiring for the RV braking monitor. The green wire will attach to your supplemental braking system. Most supplemental braking systems splice into the brake light switch to send the signal that the brake pedal is being depressed. The wire that you'll splice the green wire into is only going to be powered while the brakes are depressed.

6. Connect the black wire of the relay to the brake light wire near the brake light itself using the included blue butt connector.

7. Identify a fuse that is only powered when the ignition is in the "run" position and not when it is in the "tow" position.

8. 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.

9. Using the attached blue butt connector, connect the red wire from the brake relay to the wire from the fuse tap.

10. Ground the white wire to your towed vehicle's frame.

11. Secure the relay with the included wire ties.

I've attached an installation video below where Robert does a great job of showing a normally open wiring installation. If you have more questions please feel free to reach back out.