2008 FORD F250 brakes

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.
The TBC user interface consists of
the following:
1.+/- (GAIN adjustment
buttons):Pressing these buttons
will adjust 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 will raise or lower the setting continuously.
2.Trailer connection indicator:This lamp indicates trailer electrical
connection status.
•When a successful trailer connection is detected, the indicator will be
green.
•If the electrical connection is lost, the indicator will flash red. If the
connection is lost while the vehicle is stationary, the indicator will turn
off after 30 seconds. If the connection is lost while the vehicle is
moving, the indicator will flash until the ignition is turned off, then on
again or if there is a reconnection.
•If no electrical connection is detected after the ignition is turned on,
pressing a GAIN adjustment button will display the GAIN setting.
Sliding the manual control will display the GAIN setting, OUTPUT bar
graph and light the trailer indicator red.
3.GAIN setting display:Shows the current GAIN setting. This will
illuminate when a trailer is connected, flash if the trailer becomes
disconnected, or remain off if no trailer is connected.
4.OUTPUT bar graph:When the vehicle’s brake pedal is pushed, or
when the manual control is activated, green bar indicators will illuminate
to indicate the amount of power going to the trailer brakes relative to
the brake pedal or manual control input.
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5.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 followingProcedure for adjusting GAINsection 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 will illuminate
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 will also illuminate both
trailer and vehicle brake lamps.
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.
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.
Procedure for adjusting GAIN:
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 connection
indicator will illuminate green on the TBC and the GAIN setting display
will illuminate.
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.
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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 messages:
The TBC interacts with the instrument cluster message center. These
messages, accompanied by a single chime, will be displayed when the
TBC determines a malfunction in the trailer connection, TBC system, or
in the trailer. These messages are listed below:
TRAILER DISCONNECTED (if equipped with message center) or
CHECK TRAILER (if equipped with mini message center):This
message is displayed 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 trailer fault occurs
causing the trailer to appear disconnected. This message is also
displayed during manual activation without a trailer connected.
TBC FAULT:This message is displayed in response to faults sensed by
the TBC. In the event this message is seen, please take your vehicle to
an authorized dealer for diagnosis and repair. The TBC may still function,
but performance may be degraded.
WIRING FAULT ON TRAILER:The TBC is capable of determining
certain faults in the vehicle wiring and trailer wiring/brake system. These
faults do not mean there is anything wrong with the TBC. This message
is displayed when one of the following faults has occurred:
•Short circuit on the electric brake output wire:If the TRAILER
FAULT message is displayed 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 isnotcovered under your Ford
warranty.
Points to Remember:
•Remember to adjust gain setting before using the TBC for the first
time.
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•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 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 3 (OFF) to 4
(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. See 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 (2.5 cm) 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.
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•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 lubricant if not already so
equipped. Refer toMaintenance Product Specifications and
Capacitiesin theMaintenance and Specificationschapter for the
proper axle lubricant. Remember that regardless of the rear axle
lubricant used, do not tow a trailer for the first 500 miles (800 km) of
a new vehicle, and that the first 500 miles of towing be done at no
faster than 70 mph (112 km/h) with no full-throttle starts.
•When turning make wide turns to allow trailer tires to properly clear
any obstacles.
•Be prepared for trailer sway due to buffeting when larger vehicles
pass in either direction.
Loading
•Keep the center-of-gravity low for best handling.
•Trailer loads should be evenly distributed front to back and left to
right.
•The load distribution within the trailer should be such that 10%–15%
of the trailer weight is on the hitch. (15%–25% for fifth-wheel or
gooseneck towing.)
•Never exceed truck, trailer, receiver, ball, tongue, tire or coupler
loading recommendations.
Braking
•The trailer brakes must be inspected and serviced at intervals
specified by the manufacturer. This includes the shoes, drum and
trailer brake magnets.
•Electric brakes also require periodic adjustment to keep the shoes
properly spaced. If the brakes get hot when driving or if they will not
hold, chances are that they need adjustment.
•Anticipate the need to stop; allow much more distance and time to
stop than normal.
•Do not apply the trailer brakes for extended periods of time as they
can overheat and lose effectiveness.
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How to Use the Engine Block Heater
Ensure the receptacle terminals are clean and dry prior to use. To clean
them, use a dry cloth.
Depending on the type of factory installed equipment, your engine block
heater system may consume anywhere between 400 watts or 1000 watts
of energy per hour. Your factory installed block heater system does not
have a thermostat; however, maximum temperature is attained after
approximately 3 hours of operation. Block heater operation longer than 3
hours will not improve system performance and will unnecessarily use
additional electricity.
Make sure system is unplugged and properly stowed before driving the
vehicle. While not in use, make sure the protective cover seals the
prongs of the engine block heater cord plug.
BRAKES
Occasional brake noise is normal. If a metal-to-metal, continuous grinding
or continuous squeal sound is present, the brake linings may be worn-out
and should be inspected by your authorized dealer. If the vehicle has
continuous vibration or shudder in the steering wheel while braking, the
vehicle should be inspected by your authorized dealer.
Refer toBrake system warning
lightin theInstrument Cluster
chapter for information on the brake
system warning light.
Four-wheel anti-lock brake system (ABS)
Your vehicle is equipped with an Anti-lock Braking System (ABS). This
system helps you maintain steering control during emergency stops by
keeping the brakes from locking. Noise from the ABS pump motor and
brake pedal pulsation may be observed during ABS braking and the
brake pedal may suddenly travel a little farther as soon as ABS braking is
done and normal brake operation resumes. These are normal
characteristics of the ABS and should be no reason for concern.
P!
BRAKE
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2. Apply the brake. Use a tool (or a
small screwdriver) to pry out the
access cover. Insert the tool into the
access hole and slide the white
override button towards the left.
Move the gear shift lever into N
(Neutral) while holding the white
override disc towards the left.
When the key is in the ignition and in the OFF position, the
automatic transmission shift lever can be moved from the P
(Park) position without the brake pedal depressed. To avoid unwanted
vehicle movement, always set the parking brake.
3. Start the vehicle.
If it is necessary to use the above procedure to move the gearshift lever,
it is possible that a fuse has blown or the vehicle’s brakelamps are not
operating properly. Refer toFuses and relaysin theRoadside
Emergencieschapter.
Do not drive your vehicle until you verify that the brakelamps
are working.
Always set the parking brake fully and make sure the gearshift is
latched in P (Park). Turn the ignition to the LOCK position and
remove the key whenever you leave your vehicle.
If the parking brake is fully released, but the brake warning lamp
remains illuminated, the brakes may not be working properly.
See your authorized dealer as soon as possible.
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transmission is in P (Park) or the manual transmission is in gear. Do not
leave the vehicle unattended with the transfer case in the N (Neutral)
position. Always set the parking brake fully and turn off the ignition
when leaving the vehicle.
Always set the parking brake fully and make sure the gearshift is
latched in P (Park). Turn the ignition to the LOCK position and
remove the key whenever you leave your vehicle.
If the parking brake is fully released, but the brake warning lamp
remains illuminated, the brakes may not be working properly.
See your authorized dealer.
4WD Systems
4WD (when you select a 4WD mode), uses all four wheels to power the
vehicle. This increases traction, enabling you to drive over terrain and
road conditions that a conventional two-wheel drive vehicle cannot.
Power is supplied to all four wheels through a transfer case. On 4WD
vehicles, the transfer case allows you to select 4WD when necessary.
Information on transfer case operation and shifting procedures can be
found in theDrivingchapter. Information on transfer case maintenance
can be found in theMaintenance and Specificationschapter. You
should become thoroughly familiar with this information before you
operate your vehicle.
Normal characteristics
On some 4WD models, the initial shift from two-wheel drive to 4x4 while
the vehicle is moving can cause some momentary clunk and ratcheting
sounds. This is the front drivetrain coming up to speed and the
automatic locking hubs engaging and is not cause for concern.
Sand
When driving over sand, try to keep all four wheels on the most solid
area of the trail. Avoid reducing the tire pressures but shift to a lower
gear and drive steadily through the terrain. Apply the accelerator slowly
and avoid spinning the wheels.
Avoid excessive speed because vehicle momentum can work against you
and cause the vehicle to become stuck to the point that assistance may
be required from another vehicle. Remember, you may be able to back
out the way you came if you proceed with caution.
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