2005 FORD F650 air condition

The reserve system provides reduced braking power, so the vehicle
should be operated under these conditions with caution, and only to seek
service repair and remove the vehicle from the roadway.
For Hydromax, under normal operating conditions noise of the fluid
flowing through the booster may be heard whenever the brake is applied.
This condition is normal. Vehicle service is not required.
If braking performance or pedal response becomes very poor, even when
the pedal is strongly applied, this may indicate the presence of air in the
hydraulic system or fluid leakage. Stop the vehicle safely as soon as
possible and seek service immediately.
If the red BRAKE warning lamp in
the instrument cluster remains
illuminated after engine start up,
this indicates a system failure in the
master cylinder of the brake system. Stop the vehicle safely as soon as
possible and seek service immediately.
If the yellow BRAKE RESERVE
(E-motor) warning light remains on
while the engine is running, this
indicates inadequate hydraulic
booster pressure or reserve pump
system failure. Stop the vehicle safely as soon as possible and seek
service immediately.
BRAKE
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AIR BRAKES (IF EQUIPPED)
Foot service brakes
Air brakes are operated by a
standard dash-mounted foot pedal.
All standard equipment brakes are
designed to be self-adjusting.
Automatic adjustment, when
required, occurs whenever the
brakes are applied and released
during forward or reverse operation.
Know the required stopping
distances for all driving conditions
that may be encountered. For longer brake lining life, take full advantage
of engine braking power when coming to a stop.
Before descending a long or steep hill, shift to a lower gear and avoid
continuous application of the brakes. Normally, choose the same gear to
descend the hill that you would use to ascend the hill.
Do not drive with your foot resting on the brake pedal. This will
result in abnormally high brake temperatures, excessive lining
wear and increased stopping distances.
Continuous application of the brakes will cause the brakes to
overheat, resulting in a temporary loss of braking.
Occasional or intermittent brake squeal or groan may result from
environmental conditions such as cold, hot, wet, snow, salt, mud, etc.
This condition will not affect braking effectiveness. The brakes should be
checked only if squeal occurs continuously with every application.
If brakes do not grip well
•If you have been driving through deep water, gently apply the brakes
several times while the vehicle is moving slowly.
•Let the brakes cool if you have been using them excessively, as in
mountain driving or after several fast, high speed stops.
•Check brake adjustment.
•Check brake linings for excessive wear.
•Check system air pressure.
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Periodically check the air pressure
gauge while driving. Pressure should
range between approximately
100–125 psi (690–862 kPa). The air
compressor governor cut-in and
cut-out pressure settings are preset
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 condition may be caused by excessive brake applications depleting
the system air pressure. If this condition occurs, stop driving the vehicle
until the compressor has fully recharged the air system.
Do not move the vehicle in this condition because the brake
system may be inoperative.
Select a gear ratio to help slow your vehicle before descending grades.
Supplement with brakes as required to safely slow the vehicle and avoid
overspeeding the engine.
Air chamber stroke indication
Air chamber push rods have orange stroke indicator stripes that alert the
operator when the braking system requires adjustment or repair. The
orange stripe is painted on the air chamber push rod at the slack
adjuster readjustment stroke dimension.
Air brake inspection and adjustment should be performed by a qualified
service technician in accordance with the instructions in the service
manual.
0 30 12090 60
150AIR
PRESSUREPSI
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vehicle will be adversely affected. Repairs should be made immediately
to an inoperative air brake system circuit.
Parking brake control (knob)
Pull the yellow parking brake knob
out to apply the parking brake. Push
the knob in to release the parking
brake.
This control is used for
parking only. Do not leave
the vehicle unattended after
setting the parking brake without
placing the transmission in R
(Reverse) for manual
transmission, N (Neutral) for
automatic transmission (except
Allison 2400 transmission) or P
(Park) (Allison 2400
transmission). Use of wheel
chocks is also recommended in
hilly or off-road usage.
The parking BRAKE warning lamp
in the instrument cluster illuminates
and remains illuminated (when the
ignition is turned ON) until the
parking brake is released.
Releasing spring brake with air pressure
The air system in all vehicles with spring-actuated rear wheel parking
brakes is equipped with a tank valve located on the supply or service air
tank for connection to an outside air supply. The valve permits the
system to be recharged with air from an outside source, releasing the
spring-actuated parking brakes. The vehicle may then be towed in an
emergency.
An outside air source can be used only if the protected system is in
operating condition. If air pressure cannot be restored in the protected
air system, the spring-actuated brakes must be released manually.PARKING
BRAKE
PULL TO
RELEASE
APPLY
PUSH TO
P
BRAKE
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4. Turn the release stud one-quarter
turn to engage the stud tangs with
the slot in the pressure plate. Keep
the stud engaged and install the nut
on the release stud.
5. Tighten the nut until the spring is
fully caged and the brakes are
released. Do not loosen or remove
the release stud and nut unless the brake chamber is completely
assembled and is securely clamped.
6. When the air pressure is restored, unscrew and remove the release
stud and install in the carrying pocket. Install the access plug.
Exhaust brake (if equipped)
Note:The exhaust brake is a
retarding device intended to help
control vehicle speed; it is not a
vehicle stopping device.
An exhaust brake is an optional
auxiliary braking system that assists,
but does not replace, the primary
service brake system. An on-off
switch on the instrument panel, in
combination with the accelerator
and clutch pedal switches, allows the operator to make maximum use of
the exhaust brake in the following conditions:
•off-highway driving
•mountain driving
•heavy traffic
•high speed highway driving
Note:The exhaust brake should be turned off when the engine is left
idling for an extended period of time (longer than three minutes).
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•Depending on the grade and vehicle load, you may or may not feel the
retarding force acting against your body when the brake is applied.
The brake’s retarding force is actually preventing the vehicle from
going much faster.
•Engine speed has a major effect on retarding performance, with higher
engine speeds permitting greater retarding ability.
•Engine brake performance is closely related to the type of
transmission your vehicle is equipped with. Downshifting of manual
transmission to the lowest gear possible, without exceeding the
maximum engine RPM limit, will maximize retarding performance.
Exhaust brakes will operate effectively with automatic transmissions,
but performance will vary with engine speed and the gear selected by
the transmission.
Make sure the exhaust brake is turned off before shutting off the engine.
Note:Installing an exhaust or auxiliary brake does not necessarily
protect the engine from exceeding maximum governed speed. The
primary brakes should be used to never allow the engine to exceed
maximum governed speed under any conditions.
Trailer brake hand control (if equipped)
The hand control, located on the
right-hand side of the instrument
panel, is used to apply the trailer
service brakes which are
independent of the truck or tractor
service brakes.
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 operates a valve that provides gradual control of air
pressure applied; when the valve is only partially applied, the trailer
brakes can be overridden by pressing fully on the brake pedal.
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Actuation of trailer park (emergency) or tractor bobtail position
To actuate the trailer brakes only, pull out the trailer air supply knob (1).
The trailer brakes are now applied whether emergency or spring brakes
are used on the trailer.
This mode is also used when the tractor or truck with trailer is used
during bobtail operation.
ANTI-LOCK BRAKE SYSTEM (ABS)
Four-wheel anti-lock brake system (ABS)
A noise from the hydraulic pump motor and pulsation in the pedal may
be observed during ABS braking events. Pedal pulsation coupled with
noise while braking under panic conditions or on loose gravel, bumps,
wet or snowy roads is normal and indicates proper functioning of the
vehicle’s ABS. If the vehicle has continuous vibration or shudder in the
steering wheel while braking, the vehicle should be inspected by a
qualified service technician.
The ABS operates by detecting the
onset of wheel lockup during brake
applications and compensating for
this tendency. The wheels are
prevented from locking even when
the brakes are firmly applied. The
accompanying illustration depicts
the advantage of an ABS equipped
vehicle (on bottom) to a non-ABS
equipped vehicle (on top) during hard braking with loss of front braking
traction.
1
2
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When the Traction Controlswitch, located on the instrument panel, is
in the off position, the traction control light will be illuminated.
If you should become stuck in snow or ice or on a very slippery road
surface, try switching the Traction Controlsystem off. This may allow
excess wheel spin to“dig”the vehicle out and enable a successful
“rocking”maneuver.
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 occurrence of a Traction Control
event 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.
AIR SUSPENSION (IF EQUIPPED)
Note:The vehicle must not be operated without air in the suspension
springs. Operating the vehicle without air in the air suspension springs
will damage the suspension, degrade ride performance and may cause
property damage.
The suspension system automatically adjusts to different loads to
maintain a constant frame height. The system allows for ease of vehicle
loading and provides improved vehicle ride and increased driver comfort.
Air suspension dump switch (if equipped)
The system is controlled by a switch
located on the instrument panel.
The switch will operate only when
the ignition is in the ACC
(Accessory) or IGNITION positions
and the air tanks have sufficient
pressure to fill the air springs. When
the ignition is turned off, the
suspension will remain in whatever
state it was last set.
Note:The suspension will dump air when the ignition is in the ACC or
IGNITION position, but will only fill when the ignition is in the IGNITION
position.
When the upper portion of the switch is pressed and the vehicle speed is
below 5 mph (8 km/h), air supplied to the air spring is exhausted,
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