What Wire Does Red Wire of Roadmaster Brake Lite Relay Connect To
Updated 02/24/2026 | Published 02/21/2026
Question:
Im installing a Roadmaster brake light relay RM 88400 on a 2019 f 150. Does the red wire connect to the brake light wire brown ? Thanks
asked by: Jerry W
0
Expert Reply:
Hey Jerry, when installing the Roadmaster Brake Lite Relay part # RM-88400 the red wire runs to the running light circuit which is typically a brown wire. In the diagram it's being called the taillight circuit but that's same thing as running light.
expert reply by:
Jameson C
0
Wiring Diagram
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(click to enlarge)
Product Page this Question was Asked From
Roadmaster Brake-Lite Relay Kit for Towed Vehicles
- Flat Tow Brake System
- Brake Light Relay
- Roadmaster
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Jerry W.
2/24/2026
Thank you for the information