Mack M359, Руководство пользователя

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STARTING AND DRIVING
ANTI-LOCK BRAKING SYSTEM
WARNING
For proper ABS operation, DO NOT
change tire sizes. The size of the tires
installed during production is programmed
into the electronic control unit. Installing
different sized tires could result in a
reduced brake force, leading to longer
stopping distances or accidents.
The vehicle has a standard brake
system, equipped with an electronic
speed monitoring and control system,
Anti-lock Braking System (ABS). ABS
monitors wheel speed continuously but
is not involved in controlling the wheel
speed unless there is an emergency. In
normal braking applications, the
standard air brake system is in effect.
There is a sensor installed in each wheel
on a monitored axle. The sensors
transmit information to the electronic
control unit (ECU). The ECU interprets
the signals and calculates wheel speed,
wheel retarding and a vehicle reference
speed. If the calculations indicate a
wheel lock-up situation, a signal is sent
from the ECU to the appropriate ABS
modulator valve to reduce braking
pressure. During emergency braking, the
modulator valve alternately reduces,
increases or maintains air pressure in
the brake chamber to prevent wheel
lock-up.
During emergency or reduced-traction
stops, fully depress the foot brake pedal
until the vehicle comes to a safe stop.
DO NOT PUMP the brake pedal. With
the brake pedal fully depressed, the ABS
controls all wheels to provide steering
control and a reduced braking distance.
Although the ABS improves vehicle
control during emergency braking
situations, the operator still has the
responsibility to change driving styles
depending on the existing traffic, road
and/or weather conditions. For example,
the ABS cannot prevent an accident if
the driver is speeding or following too
closely on slippery surfaces.
The ABS control unit contains a self-
testing program that is engaged each
time the ignition is turned on. The
operator can verify the testing by
listening for the ABS modulator valves
actuating twice in series. To increase the
sound, hold down the foot brake pedal
when the ignition is turned on.
If any of the ABS tell-tales come on
during driving or do not go out after a
short time after turning on the ignition,
take the vehicle to an authorized dealer
to repair the ABS or brake system. The
vehicle can still be driven with a problem
in the ABS system. However, ABS is
disengaged and the standard braking
system operates only.
ABS Malfunction Tractor Telltale
The instrument cluster also contains an
ABS tell-tale lamp, which indicates when
a Trailer ABS system issue occurs.
ABS Malfunction Trailer Telltale
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