Ford E-350 (2010 year). Manual — part 47

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 lockup 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 in 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
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.

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

ABS, in order to reduce the likelihood of trailer wheel lockup.
Therefore, if these systems are not functioning properly the TBC may
not function at full performance.

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

display is shut down. Reactivation of the ignition from OFF to ON will
awaken 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.

Trailer lamps

Trailer lamps are required on most towed vehicles. Make sure all running
lights, brake lights, turn signals and hazard lights are working. Contact
your authorized dealer or trailer rental agency for proper instructions
and equipment for hooking-up trailer lamps.

Using a step bumper (if equipped)

The rear bumper is equipped with an integral hitch and only requires a
ball with a one inch (25.4 mm) shank diameter. The bumper has a
5,000 lb (2,270 kg) trailer weight and 500 lb (227 kg) tongue weight
capacity.

If it is necessary to relocate the trailer hitch ball position, a
frame-mounted trailer hitch must be installed.

Driving while you tow

When towing a trailer:
• To ensure proper break-in of powertrain components, do not trailer

tow during the first 1,000 miles (1,600 km) of a new vehicle.

• Do not drive faster than 70 mph (113 km/h) during the first 500 miles

(800 km) of trailer towing and don’t make full-throttle starts.

• Turn off the speed control. The speed control may shut off

automatically when you are towing on long, steep grades.

• Use a lower gear to eliminate excessive shifting and assist in

transmission cooling. For additional information, refer to Automatic
transmission operation in the Driving chapter.

• Allow more distance for stopping with a trailer attached; anticipate

stops and brake gradually.

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When descending long, steep downhill grades, always use a lower gear to
provide engine braking to save wear on brakes. Use D (Overdrive OFF)
on moderately steep hills, 2 (Second) on steep hills, and 1 (First) on
very steep hills. Do not apply your brakes continuously, as they
may overheat and become less effective.

Servicing after towing

If you tow a trailer for long distances, your vehicle will require more
frequent service intervals. Refer to your scheduled maintenance
information for more information.

Trailer towing tips
• The trailer tongue weight should be 10–15% of the loaded trailer

weight.

• Practice turning, stopping and backing-up before starting on a trip to

get the feel of the vehicle-trailer combination. When turning, make
wider turns so the trailer wheels will clear curbs and other obstacles.

• To aid in engine/transmission cooling and A/C efficiency during hot

weather while stopped in traffic, place the gearshift lever in P (Park).

• After you have traveled 50 miles (80 km), thoroughly check your

hitch, electrical connections and trailer wheel lug nuts.

• If you will be towing a trailer frequently in hot weather, hilly

conditions, at GCWR, or any combination of these factors, consider
refilling your rear axle with synthetic gear lube if not already so
equipped. Refer to the Maintenance and Specifications chapter for
the lubricant specification. Remember that regardless of the rear axle
lube used, do not tow a trailer for the first 1,000 miles (1,600 km) of a
new vehicle, and that the first 500 miles (800 km) of towing be done
at no faster than 70 mph (113 km/h) with no full throttle starts.

• Do not tow a trailer for the first 500 miles (800 km) after changing

the rear axle lube.

• Vehicles with trailers should not be parked on a grade. If you must

park on a grade, place wheel chocks under the trailer’s wheels.

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191

Launching or retrieving a boat

Disconnect the wiring to the trailer before backing the trailer
into the water. Reconnect the wiring to the trailer after the
trailer is removed from the water.

When backing down a ramp during boat launching or retrieval:
• Do not allow the static water level to rise above the bottom edge of

the rear bumper.

• Do not allow waves to break higher than 6 in (15 cm) above the

bottom edge of the rear bumper.

Exceeding these limits may allow water to enter vehicle components:
• Causing internal damage to the components.
• Affecting driveability, emissions and reliability.
Replace the rear axle lubricant any time the axle has been submerged in
water. Rear axle lubricant quantities are not to be checked or changed
unless a leak is suspected or repair required.

RECREATIONAL TOWING

Follow these guidelines if you have a need for recreational (RV) towing.
An example of recreational towing would be towing your vehicle behind
a motorhome. These guidelines are designed to ensure that your
transmission is not damaged.

Do not tow your vehicle with any wheels on the ground, as vehicle or
transmission damage may occur. It is recommended to tow your vehicle
with all four (4) wheels off the ground such as when using a car-hauling
trailer. Otherwise, no recreational towing is permitted.

In case of a roadside emergency with a disabled vehicle, see Wrecker
towing in the Roadside Emergencies chapter.

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