PREVOST X3-45 COMMUTER 2018 Operator'S Manual Download

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5-28 OTHER FEATURES

PA1633 X3-45 Commuter Operator’s Manual

The basis of ABS is constant monitoring of
wheel parameters during braking. Sensors on
each wheel of the front and drive axles
constantly measure wheel speed during braking.
This information is transmitted to a four-channel
electronic processor which senses when any
wheel is about to lock. Modulating valves quickly
adjust brake pressure (up to 5 times every
second) to prevent wheel lock. Each wheel is
therefore controlled according to the available
grip.

In this way, the vehicle is brought to a stop in the
shortest possible time while remaining stable
and under the driver's control.

WARNING

Vehicles following ABS-equipped vehicles
may not be able to brake as fast on slippery
roads.

KNEELING SYSTEM

This system lowers the front end, enabling
passengers to get on and off the coach without
any difficulty.

NOTE

This coach is equipped with an interlock
system which automatically applies the
parking brake when the kneeling system is
activated.

To operate, stop the coach, set the transmission
to neutral (N), then push down the rocker switch
located on the dashboard. (Refer to "Controls &
Instruments" section). The parking brake will be
applied automatically and a status line pictogram
will appear on the DID to indicate that the front
of the coach is being lowered.

To raise the front of the coach to its normal
height, push up the rocker switch. The front end
will rapidly rise up. The system will release the
parking brake and shift the transmission to the
previously selected range.

CAUTION

Avoid parking the coach too close to the
sidewalk or to other obstacles which could
damage the coach during kneeling.

NOTE

Kneeling is disabled when the entrance door
is open.

NOTE

The kneeling system does not operate when
the coach is traveling over 5 mph (8 km/h).
Consequently, the driver cannot inadvertently
operate the kneeling system at higher speeds.

UNLOADING TAG AXLE (OPTIONAL)

To reduce the turning radius, the air springs
pressure will be automatically reduced by 75%
when the coach is moving at speed lower than 5
mph (8 km/h) and with more than 1½ turn from
the steering.

RETRACTABLE TAG AXLE

The standard tag axle retraction system is
controlled by a valve located in the front service
compartment. The valve can be switched to
either the WHEELS UP or WHEELS DOWN
position. The axle will be raised or lowered by air
pressure according to the valve position.

The tag axle service brakes operate only when
the tag axle is in the WHEELS DOWN position.
Never lower the tag axle while the coach is
moving. When the tag axle is in the WHEELS
UP position, the corresponding  status line
pictogram will appear in the DID.  An audible
alarm will sound to warn the driver if the vehicle
speed exceeds 12 mph (20 km/h) with tag axle
raised.  The tag axle can be raised in tight
maneuvering areas like in a parking lot or to
make it easier to turn a short corner.  The tag
axle shortens the wheelbase and allows tighter
turning.  Raising the tag axle transfers extra
weight and additional traction to the drive wheels
providing improved control on slippery roads.

CAUTION

Do not use tag axle in raised position for an
extended period. Raising tag axle increases
load on the drive axle, suspension and tires.

Do not drive vehicle with tag axle raised when
speed is exceeding 12 mph (20 km/h).

In order to prevent damage to the suspension,
always raise the tag axle before lifting the
coach.