Normal Operation
WARNING: This page is about a different car, the 2007 Ford Pickup, 2007 Ford F550 Super Duty, 2007 Ford F450 Super Duty, and 2007 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The braking energy that is provided to the trailer is varied with a pulse width modulated (PWM) signal that switches between 0 volt and battery voltage, according to the TBC gain setting, the higher the duty cycle the more braking power available. With the vehicle stationary and with the manual slider switch fully to the left with a gain of 10, there should be greater than 10-12 volts supplied to trailer tow C4099-3 circuit 43 (DB).
Possible Causes
- Circuit open
- Corrosion
- Pushed-out pins
- TBC module