Test E: The Trailer Brake Control (TBC) Module Is Inoperative
PINPOINT TEST E: THE TRAILER BRAKE CONTROL (TBC) MODULE IS INOPERATIVENormal Operation
The TBC module receives fused battery power from central junction box (CJB) fuses 101 (30A) and 28 (10A) along circuits 50 (RD) and 298 (VT/OG), respectively. The ground path for the TBC module is along circuit 206 (WH). 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
^ Fuse(s)
^ Circuit open
^ Corrosion
^ Pushed-out pins
^ TBC module
E1-E4:
E4-E6:
E6-E7:
