HWH 680 Series Operator's Manual page 6

NOTE: The ignition must be in the "ON" position to use the "AIR"
button. Once the operation is started, the ignition can be moved
to the "OFF" position and the operation will continue.
1. Place the transmission in the proper position for parking and
set the park brake. The air leveling system can only be turned
on if the ignition is in the "ON" position. Leaving the engine running
during leveling is recommended. This will provide a better air
supply for leveling. The vehicle will level with the engine shut off,
however more time will be required for leveling.
NOTE: If the ignition key is in the "ON" position, the panel
will not turn on if the park brake is not set. The "NOT IN PARK/
BRAKE" light will come on while the "AIR" button is being
pushed.
2. Press the "AIR" button once to enter the air mode. The AIR
OPERATION indicator light will glow steady. When the ignition is
in the "ON" position, the four red WARNING lights on the panel
will come on. This indicates that the height control valves have
have been locked out. The vehicle should not be moved when
these lights are on.
3. Press the "AIR" button a second time. The AIR OPERATION
indicator light will start flashing and air leveling will begin. The
system will attempt to level the vehicle by exhausting air from
OPERATING PROCEDURES
AIR OPERATION
AUTOMATIC AIR OPERATION
the air bags. If a level position is not achieved by lowering the
vehicle, the low side and/or end of the vehicle will be raised by
adding air to the air bags. When all four LEVEL SENSING lights
are out the leveling is complete. The AIR OPERATION indicator
light will stop flashing, but will remain on. If there are no LEVEL
SENSING lights on when air leveling is started, the AIR OPER-
ATION indicator light will flash for 3 seconds and then will be
on steady.
When the AIR OPERATION indicator light is on steady, the
processor will be in a sleep mode for 30 minutes. The light
will remain on. The vehicle's engine may now be turned off.
After 30 minutes the processor will recheck the level indicators.
If a level indicator is observed for 1 minute, the AIR OPERA-
TION indicator light will start flashing and the system will level
the vehicle and return to the SLEEP MODE. This will continue
until the system is turned off by pushing the "OFF" button or by
releasing the park brake if the ignition is in the "ON" position.
EXCESS SLOPE: The system will attempt to level the vehicle
for approximately 45 minutes. After the 45 minutes, if a LEVEL
SENSING light is still on, the "EXCESS SLOPE" light will come
on. The AIR OPERATION indicator light will be on steady, but
the system will not go into the SLEEP MODE. Turn the system
off.
NOTE: At any time the ignition switch is in the "ON" position
and the panel is off, the vehicle may return to travel height.
MP35.4725
19JAN00