freightliner PX113064S T 2016, Руководство пользователя

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Moving the right-hand stalk switch to the ’off’ position
deactivates descent control mode and resumes
cruise control, using the descent control set speed as
the cruise control set speed.
In the case of very steep grades, regenerative
braking may not be able to maintain the vehicle
speed below the set speed. In these circumstances,
the driver can apply the service brakes to slow the
vehicle below the set speed without dropping out of
descent control mode. However, after releasing the
service brakes, a new cruise set speed lower than
the original set speed is set. The driver is informed of
this new set speed by a message on the driver
display.
Hill Start Aid
The hill start aid (HSA) feature prevents the vehicle
from rolling on a slope steeper than three percent to
allow for a controlled launch.
HSA prevents a stationary vehicle in forward gear
from rolling downhill prior to continuing to drive up
the hill; HSA also prevents a stationary vehicle in
reverse gear from rolling downhill prior to continuing
to back up the hill.
HSA delays the release of service brakes until
enough torque is available to begin moving the
vehicle, up to a maximum of three seconds. If
sufficient driveline torque is not detected after three
seconds, the system audibly alerts the driver and
releases the brakes.
HSA is on by default. It can be turned off by pressing
the HSA OFF dash switch shown in
Fig. 11.5.
When hill start aid is inactive, the HSA OFF telltale,
shown in
Fig. 11.6, flashes on the driver display
screen.
To turn hill start aid on again, press the HSA OFF
switch or cycle the vehicle keyswitch.
If the hill start aid disengaged telltale appears as a
solid image on the driver display screen, there is a
fault in the system.
Hold Function
The hold function eases the strain of driving in stop-
and-go traffic by allowing the driver to "hold" the
brake without constantly applying pressure to the
brake pedal. The hold function is an extension of hill
start aid (HSA).
To activate the hold function, bring the vehicle to a
complete stop, then press the brake pedal further
toward the floor. The HOLD telltale, shown in
Fig. 11.7, illuminates on the driver display to indicate
the function is active and the vehicle’s brake lights
come on. The driver can then take their foot off the
brake pedal without releasing the service brakes.
If the brake pedal is pressed down farther, air is
added to the chamber, continuing the brake hold.
To release the brake hold, press the accelerator
pedal, engage the park brake, or rapidly apply and
release the brake pedal.
The hold function is deactivated when the HSA OFF
switch is pressed to disable HSA.
The hold function cannot be engaged if any of the
following are true:
•
the anti-lock braking system was active in
bringing the vehicle to a stop,
•
the anti-lock braking system is in a fault state,
or
f611406 04/18/2016
HSA
OFF
Fig. 11.5, Hill Start Aid Off Dash Switch
f611712a 05/16/2022
Fig. 11.6, Hill Start Aid Disengaged Telltale
f612019 03/18/2022
Fig. 11.7, Brake Hold Active Telltale
Brake Systems
11.3