freightliner S2 Operator's Manual page 87

2. Check to see that the wheel chair lift is in the
stowed position.
3.
Confirm that the wheel chair lift switch is in the
OFF position.
4. Depress the brake pedal.
5. Push the parking brake control valve in.
Transmission Shifter Interlock Release
1.
If the vehicle is equipped with a wheel chair lift,
make sure the lift is in the stowed position, and
that the wheel chair lift switch is in the OFF posi-
tion.
2. Depress the service brake pedal to move the
vehicle shifter out of the park position.
Operating the Brakes
To ensure safe operation and minimum brake wear,
follow the steps below when operating the brakes.
1. When the ignition switch is turned on, the low air
pressure warning light (pressure circle icon) illu-
minates and the emergency buzzer sounds.
1.1 Monitor the air pressure system by ob-
serving the low air pressure warning light,
the emergency buzzer, and both the pri-
mary and secondary air pressure gauges.
1.2 The warning light and buzzer shut off
when air pressure in both systems
reaches 65 to 75 psi (448 to 517 kPa).
2.
Before driving the vehicle, continue to monitor
the air pressure system until the air compressor
has built up a minimum pressure of 95 psi (655
kPa) in both the primary and secondary air sys-
tems.
3. While driving, the low air pressure warning light
and buzzer come on if air pressure drops below
65 to 75 psi (448 to 517 kPa) in either system.
3.1 If this happens, check the air system pres-
sure gauges to determine which system
has low air pressure.
3.2 Although vehicle speed can be reduced
using the service brake, either the front or
rear service brakes will not be operating,
causing a longer stopping distance.
Hydraulic and Air Brake Systems
3.3 Bring the vehicle to a safe stop and have
the air system repaired before continuing.
4.
During normal brake stops, depress the service
brake until braking action slows down the ve-
hicle. Increase or decrease the pressure on the
pedal so that the vehicle comes to a smooth,
safe stop.
IMPORTANT: In the event of a total loss of ser-
vice brakes, use the parking brake control valve
to bring the vehicle to a complete stop in the
safest location possible.
5. When the forward speed of the vehicle has de-
creased almost to the idling speed of the engine,
press in the clutch pedal (on manual transmis-
sions) and shift the transmission to neutral. Apply
the parking brakes, if the vehicle is to be parked.
Do not use the spring parking brakes if the ser-
vice brakes are hot, such as after descending a
steep grade. Also, do not use the spring parking
brakes during freezing temperatures if the ser-
vice brakes are wet. To do so could damage the
brakes if hot, or cause them to freeze during cold
weather.
If the brakes are wet, drive the vehicle in low
gear and lightly apply the brakes to heat and dry
them. Allow hot brakes to cool before using the
spring parking brakes. Always chock the tires.
Caging the Parking Brakes
Do not drive the vehicle with the parking brakes
caged. If the vehicle is driven with the parking
brakes caged, there would be no means of stop-
ping the vehicle if a complete loss of air pressure
occurred. This could result in serious personal
injury or vehicle damage.
To move a vehicle with insufficient system air pres-
sure, it is necessary to release the parking brake
springs.
There are two ways to do this:
•
Apply an external air source at the gladhands;
•
Cage (manually release) the parking brakes.
NOTICE
WARNING
13.2