E 450 V8-5.4L (2009)
The IC message center displays the trailer connectivity status as well as gain setting (number display) and relative trailer braking power (output bar
graph) during a braking event. When a successful trailer connection is detected by the TBC module, the message center will display TRAILER
CONNECTED. If the electrical connection to the trailer is lost or disconnected during the same ignition cycle, the message center will display TRAILER
DISCONNECTED.
Trailer Brake Control (TBC) Module Start Up, Prove Out and Wake Up
The following information describes the normal operation of the TBC module during start up and prove out both with and without a trailer connected to
the vehicle. When the ignition key is turned to the ON position, the message center in the IC will illuminate all LED segments (prove out) for
approximately 3 seconds. At the same time, the TBC module will check for trailer connectivity, check the IC for trailer brake configuration and then
display the appropriate message in the message center.
Start Up and Prove Out Without a Trailer Connected to the Vehicle
When the ignition key is turned to the ON position and the IC is configured for trailer brakes, after the message center proves out it will display
TRAILER DISCONNECTED. Pressing a gain button or moving the manual sliding switch will cause the message center to display TBC GAIN = XX.X
NO TRAILER. XX.X being the current gain setting in the TBC module.
When the ignition key is turned to the ON position and the IC is not configured for trailer brakes, after the message center proves out the TBC module
will shut down and the system will be inoperative. Pressing the gain button or moving the manual sliding switch will cause TBC FAULT to be displayed
in the message center and a DTC will be set in the TBC module. For information on programming the IC for trailer brakes, refer to Programmable
Parameters.
Start Up and Prove Out With a Trailer Connected to the Vehicle
When the ignition key is turned to the ON position and the IC is configured for trailer brakes, after the message center proves out it will display
TRAILER CONNECTED. Pressing a gain button or moving the manual sliding switch will cause the message center to display TBC GAIN = XX.X
OUTPUT = //////. XX.X being the current gain setting in the TBC module and ////// being the current output to the trailer. One bar is the least amount of
output, 6 bars is the maximum.
If the IC is not configured for trailer brakes, the TBC module will react the same as indicated above in Start Up and Prove Out Without a Trailer
Connected to the Vehicle.
TBC Module Wake Up
With a trailer connected to the vehicle, the TBC module will remain active while the ignition key is in the ON position to monitor the vehicle and trailer
brake systems. Without a trailer connected to the vehicle, the TBC module will enter a "sleep mode" but will continue to send a PWM voltage signal to
the trailer tow connector every 4 seconds to detect when a trailer is connected.
When the ignition key is in the ON position and the module is in sleep mode, pressing a gain button or sliding the manual switch will cause the module to
"wake up". If a trailer is not connected to the vehicle, the message center display should prove out for 3 seconds and then display TRAILER
DISCONNECTED. If a trailer is connected to the vehicle, the display should prove out for 3 seconds and then display TRAILER CONNECTED.
Inspection and Verification
Auxiliary Brake System - Trailer Brake Control (TBC) Module
Inspection and Verification
NOTE: A trailer brake emulator tool is available to verify that the Trailer Brake Control (TBC) module and vehicle wiring are functioning correctly.
1. Verify the customer concern.
2. NOTE: The TBC system does not function with electric-over-hydraulic or surge trailer brake types.
Verify that the trailer brakes are electric-actuated drum type brakes.
3. Verify that the yellow ABS warning indicator shuts off after prove out. If the warning indicator operates correctly, proceed to the next step. If the
warning indicator remains illuminated, GO to Antilock Brakes / Traction Control Systems to diagnose the warning indicator. See: Antilock
Brakes / Traction Control Systems/Testing and Inspection
4. Verify the vehicle stoplamps operate correctly by applying and releasing the brake pedal with the ignition switch in the OFF position and the
trailer disconnected. If the stoplamps do not operate correctly, refer to Brake Lamp. If the vehicle stoplamps operate correctly, proceed to the next
step. See: Lighting and Horns/Brake Lamp/Testing and Inspection
