Ford E-350 (2012 year). Manual — part 44

Trailer brakes

Electric brakes and manual, automatic or surge-type trailer brakes are
safe if installed properly and adjusted to the manufacturer’s
specifications. The trailer brakes must meet local and Federal
regulations.

WARNING: Do not connect a trailer’s hydraulic brake system
directly to your vehicle’s brake system. Your vehicle may not

have enough braking power and your chances of having a collision
greatly increase.

The braking system of the tow vehicle is rated for operation at the
GVWR not GCWR.

Integrated trailer brake controller (if equipped)

Your vehicle may be equipped with a fully integrated electronic trailer
brake controller (TBC). When used properly, the TBC helps ensure
smooth and effective trailer braking by powering the trailer’s electric
brakes with a proportional output based on the towing vehicle’s brake
pressure.

WARNING: The Ford TBC has only been verified to be
compatible with trailers having electric-actuated drum brakes

(one to four axles) and not hydraulic surge or electric-over-hydraulic
types. It is the responsibility of the customer to ensure that the trailer
brakes are adjusted appropriately, functioning normally and all electric
connections are properly made. Failure to do so may result in loss of
vehicle control, crash or serious injury.

The TBC user interface consists of
the following:

1. +/- (GAIN adjustment
buttons): Pressing these buttons
adjusts the TBC’s power output to
the trailer brakes (in
0.5 increments). The GAIN setting
can be increased to a maximum of
10.0 or decreased to a minimum of 0 (no trailer braking). Pressing and
holding a button raises or lowers the setting continuously. The gain
setting displays in the message center as follows: TBC GAIN = XX.X.

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The trailer brake controller (TBC) is designed to display three items of
information in the instrument cluster message center. These are: gain
setting, output bar graph, and trailer connectivity status. They appear in
the message center as follows:
• TBC GAIN = XX.X NO TRAILER: The instrument cluster message

center displays the current gain setting during a given ignition cycle
and when adjusting the gain. This message is also displayed during
manual activation without a trailer connected or when gain
adjustments are made with no trailer connected.

• TBC GAIN = XX.X OUTPUT = //////: When the vehicle’s brake pedal

is pushed, or when the manual control is activated, bar indicators
illuminate in the instrument cluster message center to indicate the
amount of power going to the trailer brakes relative to the brake pedal
or manual control input. One bar indicates the least amount of output
with six bars indicating maximum output.

• TRAILER CONNECTED: This message is displayed when a correct

trailer wiring connection (a trailer with electric trailer brakes) has
been sensed during a given ignition cycle.

• TRAILER DISCONNECTED: This message is displayed and

accompanied by a single chime, when a trailer connection was
determined and then a disconnection, either intentionally or
unintentionally, has been sensed during a given ignition cycle. It is also
displayed if a truck or trailer wiring fault occurs causing the trailer to
appear disconnected. This message is also displayed during manual
activation without a trailer connected.

2. Manual control lever: Slide the control lever to the left to activate
power to the trailer’s electric brakes independent of the tow vehicle’s
brakes (see the following Procedure for adjusting GAIN section for
instructions on proper use of this feature). If the manual control is
activated while the brake is also applied, the greater of the two inputs
determines the power sent to the trailer brakes.
• Stop lamps: Activating the TBC manual control lever illuminates both

the trailer brake lamps and the tow vehicle brake lamps except the
center high-mount stop lamp (presuming proper trailer electrical
connection). Pressing the vehicle brake pedal also illuminates both
trailer and vehicle brake lamps.

Procedure for adjusting GAIN:

The GAIN setting is used to set the TBC for the specific towing
condition and should be changed as towing conditions change. Changes
to towing conditions include trailer load, vehicle load, road conditions
and weather.

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The GAIN should be set to provide the maximum trailer braking
assistance while ensuring the trailer wheels do not lock when braking;
locked trailer wheels may lead to trailer instability.

Note: This should only be performed in a traffic-free environment at
speeds of approximately 20–25 mph (30–40 km/h).

1. Make sure the trailer brakes are in good working condition, functioning
normally and properly adjusted. See your trailer dealer if necessary.

2. Hook up the trailer and make the electrical connections according to
the trailer manufacturer’s instructions.

3. When a trailer with electric brakes is plugged in, the TRAILER
CONNECTED message displays in the instrument cluster message
center.

4. Use the GAIN adjustment (+/-) buttons to increase or decrease the
GAIN setting to the desired starting point. A GAIN setting of 6.0 is a
good starting point for heavier loads.

5. In a traffic-free environment, tow the trailer on a dry, level surface at
a speed of 20–25 mph (30–40 km/h) and squeeze the manual control
lever completely.

6. If the trailer wheels lock up (indicated by squealing tires), reduce the
GAIN setting; if the trailer wheels turn freely, increase the GAIN setting.
Repeat Steps 5 and 6 until the GAIN setting is at a point just below
trailer wheel lock-up. If towing a heavier trailer, trailer wheel lock-up
may not be attainable even with the maximum GAIN setting of 10.

Explanation of instrument cluster warning messages:

The TBC interacts with the instrument cluster message center to display
the following messages:

TRAILER BRAKE MODULE FAULT: This message is displayed and
accompanied by a single chime, in response to faults sensed by the TBC.
In the event this message is seen, please contact your authorized dealer
as soon as possible for diagnosis and repair. The TBC may still function,
but performance may be degraded.

WIRING FAULT ON TRAILER: This message is displayed when a
Short circuit on the electric brake output wire has occurred. If the
WIRING FAULT ON TRAILER message is displayed and accompanied
by a single chime, with no trailer connected, the problem is with the
vehicle wiring from the TBC to the 7–pin connector at the bumper. If the
message is only displayed with a trailer connected, the problem is related
to the trailer wiring; consult your trailer dealer for assistance. This can

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be a short to ground (i.e., chaffed wire) or a short to voltage (i.e., pulled
pin on trailer emergency break-away battery) or trailer brakes drawing
too much current.

Note: Your TBC can be diagnosed by your authorized dealer to determine
exactly which trailer fault has occurred; however, if the fault is with the
trailer this diagnosis is not covered under your Ford warranty.

Points to Remember:
• Remember to adjust gain setting before using the TBC for the first

time.

• Readjust gain setting on the TBC (according to procedure above)

whenever road, weather and trailer or vehicle loading conditions
change from those that existed when the gain was initially set.

• The sliding lever on the TBC should be used only for manual

activation of trailer brakes to assist with proper adjustment of the
GAIN. Misuse, such as application during trailer sway, could cause
instability of trailer and/or tow vehicle.

• Avoid towing in adverse weather conditions. The TBC does not provide

anti-lock control of the trailer wheels. Trailer wheels can lock up on
slippery surfaces, resulting in reduced stability of trailer and tow vehicle.

• The TBC is equipped with a feature which reduces output at vehicle

speeds below 11 mph (18 km/h) so trailer and vehicle braking is not
jerky or harsh. This feature is only available when applying the brakes
using the vehicle’s brake pedal, not the TBC.

• The TBC interacts with the brake system of the vehicle, including

ABS, in order to reduce the likelihood of trailer wheel lock-up;
therefore, if these systems are not functioning properly, the TBC may
not function at full performance.

• Your vehicle’s brake system and the trailer brake system work

independently of each other; changing the GAIN setting on the TBC
does not affect the operation of your vehicle’s brakes whether a trailer
is attached or not.

• When the vehicle is turned off, the TBC output is disabled and the

display is shut down; turning the ignition from off to on awakens the
TBC module.

• The TBC is only a factory- or dealer-installed item; Ford is not

responsible for warranty or performance of the TBC due to misuse or
customer installation.

• Do not attempt removal of the TBC without consulting the

Workshop Manual; damage to the unit may result.

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