OTHER FEATURES
The basis of ABS is constant monitoring of
wheel parameters during braking. Sensors on
each wheel of axles 1 and 2 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 per second) to
prevent wheel lock. Each wheel is therefore
controlled according to the available grip.
In this way, the coach is brought to a stop in the
shortest possible time while remaining stable
and under the driver's control.
Caution :
Vehicles following ABS-equipped
motorcoaches may not be able to brake as fast
on slippery roads. Whenever possible, warn
other drivers by depressing the brake pedal
lightly several times before braking.
RETRACTABLE TAG AXLE
Optional tag axle retraction is controlled by a
valve located on the left lateral console. The
valve can be switched to either the WHEELS UP
or WHEELS DOWN position. The axle will be
automatically raised or lowered by air pressure
according to the valve position. Refer to
"Controls & Instruments" chapter 3.
The tag axle service brakes and parking 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 indicator light will illuminate and a
beep will sound to alert the driver of the tag
axle's position. 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 :
In order to prevent damage to the
suspension, always raise the tag axle before
lifting the motorcoach.
Caution :
Never lower the tag axle while
motorcoach is moving.
TAG LOAD RELEASE SYSTEM
(TLR)
This standard system allows automatic
unloading of the tag axle air springs, without
raising the axle, whenever coach speed drops to
less than 8 mph (13 km/h) and steer angle
exceeds 22.5° (1 1/4 turns of the steering
wheel). The system automatically transfers the
tag axle load to the drive axle. It reduces tag
wheel shearing to convey shorter turning radii for
tighter cornering and remarkable agility in close-
quarter maneuvering, whether backing up or
moving forward.
COOLANT HEATER
An optional coolant heater, the WEBASTO DBW
2020 rated at 80 000 Btu/h (23.3 Kw), is
available.
This auxiliary heating system is used for
preheating and retaining the heat of water-
cooled engines. It can be used before startup to
facilitate starting and to provide rapid operation
of the interior heating system. It can also be
used with the engine running to maintain coolant
heat and interior temperature.
The heater operates independently of the
engine. It is connected to the cooling system,
heating circuits and to the motorcoach fuel and
electrical system.
Warning :
The coolant heating system uses
the same fuel as the engine. Do not operate in a
closed building or while refueling. Operate only
in a well ventilated area.
S
WITCHING
T
HE
H
EATER
O
N
The pilot lamp turns
ON
when the heater is
switched
ON
. Combustion air flows in to flush
out the combustion chamber and the water
circulation pump begins operating. The fuel
metering pump delivers fuel in precise amounts
to the combustion chamber, where fuel and
combustion air form a combustible mixture which
is ignited by the glow plug.
Once the flame sensor has signaled to the
control unit that combustion has taken place, the
glow plug and ignition coil are switched
OFF
.
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