engine FORD F650/750 2021 Repair Manual

5. Tighten the nut until the spring is fully
caged and brakes released. Do not
loosen or remove the release stud and
nut unless you completely assemble
and securely clamp the brake chamber.
6. After restoring the air pressure, unscrew and remove the release stud
and install in the carrying pocket. Install
the access plug.
HILL START ASSIST WARNING: The system does not
replace the parking brake. When you
leave your vehicle, always apply the
parking brake. WARNING:
You must remain in
your vehicle when the system turns on.
At all times, you are responsible for
controlling your vehicle, supervising the
system and intervening, if required.
Failure to take care may result in the loss
of control of your vehicle, serious
personal injury or death. WARNING:
The system will turn
off if a malfunction is apparent or if you
rev the engine excessively. Failure to take
care may result in the loss of control of
your vehicle, serious personal injury or
death.
The system makes it easier to pull away
when your vehicle is on a slope without the
need to use the parking brake.
When the system is active, your vehicle
remains stationary on the slope for two to
three seconds after you release the brake
pedal. This allows time to move your foot
from the brake to the accelerator pedal.
The system releases the brakes
automatically once the engine has developed sufficient torque to prevent your
vehicle from rolling down the slope. This
is an advantage when pulling away on a
slope, for example from a car park ramp,
traffic lights or when reversing uphill into
a parking space.
The system activates on any slope that
causes your vehicle to roll.
Note:
There is no warning light to indicate
the system is either on or off.
Using Hill Start Assist
1. Press the brake pedal to bring your vehicle to a complete standstill. Keep
the brake pedal pressed and shift into
first gear when facing uphill or reverse
(R) when facing downhill.
2. If the sensors detect that your vehicle is on a slope, the system activates
automatically.
3. When you remove your foot from the brake pedal, your vehicle remains on
the slope without rolling away for
about two to three seconds. This hold
time automatically extends if you are
in the process of driving off.
4. Drive off in the normal manner. The system releases the brakes
automatically.
Note: When you remove your foot from the
brake pedal and press the pedal again when
the system is active, you will experience
significantly reduced brake pedal travel. This
is normal.
Switching the System On and Off
Vehicles with Manual Transmission
You can switch this feature on or off in the
information display. The system
remembers the last setting when you start
your vehicle.
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Vehicles with Automatic Transmission
You cannot turn the system on or off.
When you switch the ignition on, the
system automatically turns on.
AIR BRAKES (IF EQUIPPED)
WARNING: Do not drive or continue
to drive if the low air pressure buzzer is
sounding or the brake warning light is lit.
These warnings indicate that air pressure
is not to normal operating level.
Continued use of the vehicle could result
in loss of braking ability. WARNING:
Avoid repeated light
application of the brake pedal. This
depletes air pressure faster and could
result in loss of braking capability. WARNING:
Do not move the
vehicle when the air pressure is
insufficient because the brake system
may be inoperative.
After starting the engine, give the air
compressor time to build up the air
pressure to
60 psi (414 kPa) before moving
your vehicle. Periodically check the air pressure gauge
while driving. Pressure should range
between approximately 100 psi (690 kPa)
to
130 psi (896 kPa). The air compressor
governor cut-in and cutout pressure
settings are set at the factory and are not
adjustable. When air pressure is insufficient
(below
60 psi (414 kPa)), a
warning light illuminates and a
buzzer sounds when the ignition is in the
on position. This may happen because
excessive brake applications are depleting
the system air pressure. If this condition
occurs, stop driving your vehicle until the
compressor has fully recharged the air
system.
Select a gear ratio to help slow your vehicle
before descending grades. Supplementing
with brakes, as required, help to safely slow
the vehicle and avoids overspeeding the
engine.
Air Chamber Stroke Indication
Air chamber push rods have orange stroke
indicator markers that warn when the
braking system requires adjustment or
repair. The painted orange indicator is on
the air chamber push rod at the slack
adjuster stroke dimension that requires
service when visible during brake
application.
A qualified service technician should
perform air brake inspection and
adjustment or repairs keeping to the
instructions in the service manual.
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Cam Brakes - Automatic Slack
Adjusters
WARNING: Do not manually adjust
the automatic slack adjusters to correct
excessive push rod stroke as it may result
in reduced brake effectiveness and a
vehicle crash. Excessive push rod stroke
indicates that a problem exists with the
automatic adjuster, with the installation
of the adjuster, or with foundation brake
components that manual adjustment
does not remedy. Seek service from a
qualified facility for excessive push rod
stroke. Standard air brakes (cam) are equipped
with automatic brake adjusters. Automatic
adjustment occurs during brake
applications. Inspect brakes for proper
adjustment at the specified intervals. See
Scheduled Maintenance (page 319).
Emergency Air Brake WARNING:
Do not continue to
operate the vehicle with a failure of one
of the brake systems. Take the vehicle
to your dealer for service immediately. All vehicles are equipped with a dual brake
system. In the unlikely event of a failure of
one system, the second system functions
for emergency stopping. The brake pedal
controls all these systems in the same
manner as for normal stops.
EXHAUST BRAKE
(IF EQUIPPED)
WARNING:
Do not use tow/haul
when the road surface is slippery. Failure
to follow this instruction could result in
the loss of control of your vehicle. WARNING:
Do not use diesel
engine exhaust braking when the road
surface is slippery. Failure to follow this
instruction could result in the loss of
control of your vehicle.
Note: Installing an exhaust or auxiliary
brake does not necessarily protect the
engine from exceeding the maximum
governed speed. Use the primary brakes to
make sure the engine never exceeds the
maximum governed speed under any
circumstance.
Note: Before starting the engine, make sure
that the exhaust brake is off. Do not switch
the exhaust brake on until the engine has
reached normal operating temperature.
Note: Engine speed has a major influence
on limiting performance. When engine
speed stays at the maximum allowable
level, the exhaust brake operates at peak
performance.
Note: Exhaust brakes operate effectively
with automatic transmissions. However,
performance varies with engine speed and
the gear selected by the transmission.
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An exhaust brake is an auxiliary braking
system that assists, but does not replace,
the primary brake system. It helps control
vehicle speed. It is not a vehicle-stopping
device.
Use the button on the instrument panel, in
combination with the accelerator pedal,
to maximize the use of the exhaust brake
in the following conditions:
•
Off-highway driving.
• Mountain driving.
• Heavy traffic.
• High-speed highway driving. To switch the exhaust brake on, press the
button. A light on the instrument cluster
indicates the system is on. Press the button
again to switch it off.
While approaching a steep grade, make
sure that the exhaust brake switch is on.
The exhaust brake begins working as soon
as you remove your foot from the
accelerator pedal. Before descending a hill or steep grade,
always select the proper gear. If you take
the transmission out of gear while
descending, you may not be able to select
another gear because of maximum
governed RPM.
Make sure the engine speed does not
exceed the maximum allowable engine
RPM. Exceeding the maximum allowable
engine RPM can result in damage to the
engine. Apply the service brakes to reduce
the engine RPM or make a slower descent
by using a lower gear.
While driving down a grade, use a low
enough gear to descend safely with a
minimum application of the service brakes.
As a general guideline, use the same gear
as you use to ascend the hill.
Exhaust Brake Operating
Characteristics
The exhaust brake switches on when you
remove your feet from the accelerator
pedal and the exhaust brake is on.
If the brake is working properly, you may
notice:
•
A slight change in engine sound when
the exhaust brake turns on.
• A smooth braking effect. Do not expect
a retarding effect similar to sudden,
hard application of the service brakes.
• A retarding force possibly felt acting
against your body during brake
application, depending on the grade
and vehicle load. This force helps your
vehicle resist increasing speeds down
grades.
• Engine temperatures remaining in the
normal operating range.
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•
A drop in engine RPM, depending on
grade and vehicle load, during a
descent.
• A decrease in road speed when
applying the exhaust brake during a
descent, except when your vehicle is
carrying a heavy load or the grade is
extremely steep. In these instances,
you may need to apply the service
brakes occasionally.
TRAILER BRAKES
Trailer Brake Hand Control (If Equipped) WARNING: The hand control
should never be used to apply the brakes
when the tractor and trailer are parked
unattended. Air may leak from the
system and the vehicle could possibly
move, resulting in possible property
damage, personal injury or death. The hand control is located on the
right-hand side of the instrument panel. It
applies the trailer service brakes, which are
independent of the truck or tractor service
brakes.
It operates a valve that provides gradual
control of air pressure applied. When the
valve is only partially applied, you can
override the trailer brakes by pressing fully
on the brake pedal. To apply the trailer brakes using the hand
control, move the lever downward. The
further you push the lever down, the
greater the air pressure is applied to the
brakes. The lever remains in place until
manually moved.
To release the trailer brakes, move the
lever up completely.
Trailer Air Supply and Parking
Brake Modular Controls
(If Equipped)
The trailer air supply valve delivers air to
the trailer supply and automatically pops
out, shutting off the trailer supply, if
pressure decreases to approximately 35 psi
(249 kPa)
.
The parking brake controls the spring
brakes on the tractor. When you pull the
knob out, it causes the trailer supply valve
to pop out, applying both the tractor and
trailer parking brakes. You can
independently release the trailer brakes by
pushing only the trailer air supply valve in.
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PRINCIPLE OF OPERATION
The traction control system helps avoid
drive wheel spin and loss of traction.
If your vehicle begins to slide, the system
applies the brakes to individual wheels
and, when needed, reduces engine power
at the same time. If the wheels spin when
accelerating on slippery or loose surfaces,
the system reduces engine power in order
to increase traction.
Note:
The system does not apply the brakes
when vehicle speed is above 25 mph
(40 km/h).
USING TRACTION CONTROL -
VEHICLES WITH: AIR BRAKES WARNING:
The stability and
traction control light illuminates steadily
if the system detects a failure. Make sure
you did not manually disable the traction
control system using the information
display controls or the switch. If the
stability control and traction control light
is still illuminating steadily, have the
system serviced by an authorized dealer
immediately. Operating your vehicle with
the traction control disabled could lead
to an increased risk of loss of vehicle
control, vehicle rollover, personal injury
and death. Press the TCS Off button on the
instrument panel to enable the
mud/snow mode.
This is beneficial when your vehicle is stuck
in snow or on a slippery road surface. This
mode allows wheel spin to dig your vehicle
out and allows you to rock your vehicle. Press the switch again to select standard
traction control. The system automatically
selects standard traction control at the
next ignition cycle.
System Indicator Light
Note:
If the traction control light does not
flash during a traction control event or stays
illuminated, the system is not functioning
properly. Take your vehicle to an authorized
dealer for service.
During traction control operation, the
traction control light flashes rapidly and
the engine does not rev-up when you press
further on the accelerator. This is normal
and is no reason for concern.
In Mud/Snow mode, the TCS OFF light
illuminates on the instrument cluster. If a
traction event occurs in either mode, the
Stability Control and Traction Control light
flashes rapidly.
USING TRACTION CONTROL -
VEHICLES WITH: HYDRAULIC
BRAKES WARNING:
Aggressive driving in
any road conditions can cause you to
lose control of your vehicle increasing
the risk of severe personal injury or
property damage. The traction control
activating is an indication that at least
some of the tires have exceeded their
ability to grip the road; this may lead to
an increased risk of loss of vehicle
control, vehicle rollover, personal injury
and death. If you experience a severe
road event, slow down
.
The system turns on each time you switch
the ignition on.
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Use the traction control button
on the instrument panel to
switch the system off or on.
If your vehicle is stuck in mud or snow,
switching traction control off is beneficial
as this allows the wheels to spin.
Press the button again to switch the
traction control system on.
System Indicator Light
Note: If the traction control light does not
flash during a traction control event or stays
on, the system is not operating. Have the
system checked as soon as possible.
During a traction control event, the traction
control light rapidly flashes. Pressing
further on the accelerator does not cause
the engine to rev higher. This is normal and
is no reason for concern.
When the system turns the traction control
off, the OFF light illuminates on the
instrument cluster. If a traction event
occurs in either mode, the stability control
and traction control light rapidly flashes.
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PRINCIPLE OF OPERATION -
VEHICLES WITH: HYDRAULIC
BRAKES
WARNING: Vehicle modifications
involving braking system, aftermarket
roof racks, suspension, steering system,
tire construction and wheel and tire size
may change the handling characteristics
of your vehicle and may adversely affect
the performance of the electronic
stability control system. In addition,
installing any stereo loudspeakers may
interfere with and adversely affect the
electronic stability control system. Install
any aftermarket stereo loudspeaker as
far as possible from the front center
console, the tunnel, and the front seats
in order to minimize the risk of interfering
with the electronic stability control
sensors. Reducing the effectiveness of
the electronic stability control system
could lead to an increased risk of loss of
vehicle control, vehicle rollover, personal
injury and death. WARNING:
Remember that even
advanced technology cannot defy the
laws of physics. It's always possible to
lose control of a vehicle due to
inappropriate driver input for the
conditions. Aggressive driving on any
road condition can cause you to lose
control of your vehicle increasing the risk
of personal injury or property damage.
Activation of the electronic stability
control system is an indication that at
least some of the tires have exceeded
their ability to grip the road; this could reduce the operator's ability to control
the vehicle potentially resulting in a loss
of vehicle control, vehicle rollover,
personal injury and death. If your
electronic stability control system
activates, SLOW DOWN.
The system turns on each time you switch
the ignition on.
If a fault occurs in either the stability
control or the traction control system, the
following conditions are possible:
• The stability and traction control light
illuminate.
• The stability control and traction
control systems are not maintaining
traction of the wheels.
If a driving condition activates either the
stability control or the traction control
system, the following conditions are
possible:
• The stability and traction control light
flash.
• Your vehicle slows down.
• The system reduces engine power.
• A vibration in the brake pedal.
• The brake pedal is stiffer than usual.
• If the driving condition is severe and
your foot is not on the brake, the brake
pedal could move as the system
applies higher brake force.
The stability control system has several
features built into it to help you maintain
control of your vehicle:
Electronic Stability Control
The system assists in preventing skids or
lateral slides by applying the brakes to one
or more of the wheels individually and, if
necessary, decreases engine power.
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(If Equipped)

•
The stability control and traction
control systems do not enhance your
vehicle's ability to maintain traction of
the wheels.
If a driving condition activates either the
stability control or the traction control
system you may experience the following
conditions:
• The stability and traction control light
flashes rapidly.
• Your vehicle slows down.
• Reduced engine power.
The stability control system has several
features built into it to help you maintain
control of your vehicle:
Electronic Stability Control
The system enhances your vehicle ’s ability
to prevent skids or lateral slides by
applying brakes to one or more of the
wheels individually and, if necessary,
reducing engine power.
Roll Stability Control
The system enhances your vehicle ’s ability
to prevent rollovers by detecting your
vehicle ’s motion and the rate at which it
changes by applying the brakes to one or
more wheels individually.
Traction Control
The system enhances your vehicle ’s ability
to maintain traction of the wheels by
detecting and controlling wheel spin. See
Using Traction Control (page 142). Vehicle without stability control
skidding off its intended route.
A
Vehicle with stability control
maintaining control on a slippery
surface.
B
USING STABILITY CONTROL
(IF
EQUIPPED)
The system automatically turns on each
time you switch the ignition on.
You cannot switch the stability control and
roll stability control systems off, but when
you shift into reverse (R), the systems
deactivate.
You can switch the traction control system
off or on. See Traction Control (page 142).
Limitations of the Stability System
Stability Control effectiveness may be
greatly reduced if:
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The set speed does not erase.
Resuming the Set Speed
Press and release the button.
Your vehicle speed returns to the
previously set speed and gap setting. The
set speed displays continuously in the
information display when the system is
active.
Note: Only use resume if you are aware of
the set speed and intend to return to it.
Automatic Cancellation
The system is not functional at vehicle
speeds below 12 mph (20 km/h). The
information display indicates low engine
speed, an audible alarm sounds and the
automatic braking releases if the vehicle
drops below this speed.
Automatic cancellation can also occur
when:
• The tires lose traction.
• You apply the parking brake.
Note: If the engine speed drops too low, an
audible warning sounds and a message
appears in the information display.
Automatic braking releases.
Hilly Condition and Trailer Tow
Usage
You should select a lower gear when the
system is active in situations such as
prolonged downhill driving on steep
grades, for example in mountainous areas.
The system needs additional engine
braking in these situations to reduce the
load on the vehicle ’s regular brake system
to prevent it from overheating. Note:
An audible alarm sounds and the
system shuts down if it applies brakes for
an extended period of time. This allows the
brakes to cool. The system functions
normally again after the brakes cool.
Note: When towing with adaptive cruise
control, switch on Tow/Haul Mode and
Diesel Engine Brake.
Switching Adaptive Cruise Control
Off Press and release the button
when the system is in standby
mode, or switch the ignition off.
Note: You erase the set speed and gap
setting when you switch the system off.
Detection Issues WARNING: On rare occasions,
detection issues can occur due to the
road infrastructures, for example bridges,
tunnels and safety barriers. In these
cases, the system may brake late or
unexpectedly. At all times, you are
responsible for controlling your vehicle,
supervising the system and intervening,
if required. WARNING:
If the system
malfunctions, have your vehicle checked
as soon as possible.
The radar sensor has a limited field of
view. It may not detect vehicles at all or
detect a vehicle later than expected in
some situations. The lead vehicle graphic
does not illuminate if the system does not
detect a vehicle in front of you.
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