Auxiliary Brake System - Vehicles With: Trailer Brake Control - Overview
WARNING: This page is about a different car, the 2019 Ford F-550 Super Duty, 2019 Ford F-450 Super Duty, 2019 Ford F-350 Super Duty, and 2019 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
Trailer Brake Control
The trailer brake system uses an ECU called the TBM to provide variable braking power to the electric-actuated brakes on a towed trailer (1 to 4 axles only). The braking energy provided to the trailer is modulated with a PWM signal varying between 0 volt and battery voltage, the higher the duty cycle the more braking power available.