MI91.1165
01SEP15
SYSTEM OPERATION
The 625 Single Step leveling system is a computer controlled, BI-AXIS push button system. This system has automatic or
optional manual control. This system will always extend two (2) jacks at the same time in the automatic or manual mode, both
front jacks, the left front and left rear jacks, the right front and right rear jacks or both rear jacks. In the manual mode, the jacks
are controlled by the UP and DOWN arrow buttons on the right hand side of the touch panel. The UP arrows extend jack pairs
and the DOWN arrows retract jack pairs.
If the vehicle is equipped with an air suspension, the air must be exhausted from the suspension before leveling the vehicle. If
the air is not exhausted, the suspension height control valves will interfere with the leveling procedure. There are two types of
air dump systems that HWH controls. One system uses air solenoid valves supplied by HWH. The second system is supplied
by the chassis manufacturer. This is a pilot air dump system. In the automatic mode, the air is dumped automatically before
the leveling process is started. For manual leveling, the HWH touch panel has a "DUMP" button. The "DUMP" button will work
if the ignition is on and the park brake is set. If the vehicle uses the HWH air dump valves, the "DUMP" button must be pushed
and held until all of the air is exhausted from the vehicle suspension system. The engine must be off. If a pilot air dump system
is used, the engine may be on or off. The "DUMP" button can be pushed and released. The pilot air dump system will return to
the travel position if the ignition is on and the "STORE" button is pushed or the park brake is released.
AUTOMATIC OPERATION
Push the "AUTO LEVEL" button one time. The AUTO LEVEL light will flash.
On the right hand side of the touch panel there are four (4) red and four (4) yellow indicator lights. The four red indicator lights
are JACK DOWN warning lights. There is one light for each jack. These warning lights come on when their respective jacks
are extended about 1/4 to 1/2 inch. The four yellow indicator lights are level indicators, front, left side, right side and rear. A lit
yellow level light indicates that a side, end or corner is low. When all four yellow level lights are out, the vehicle is level within
the tolerance of the level sensing unit.
The computer will extend jack pairs according to the level lights starting with a lit side light. When all four level lights are out,
the computer will extend any jacks not used for leveling to stabilize the vehicle. The computer looks for a jack pressure switch
from each jack to know all jacks are on the ground. NOTE: Both front solenoid valves will come on during the stabilize
procedure when either front jack pressure switch is not on. When both front jack pressure switches are on, both front
solenoid valves will be off.
There are two parts to leveling a vehicle. First the vehicle is leveled. The jacks are used to turn all the yellow level indicators
off. The second part of leveling is to stabilize the vehicle. This is accomplished by extending any jacks not used for leveling to
the ground and lifting the vehicle between 1/4 to 3/4 inch.
NOTE: Releasing the park brake to return the suspension to travel mode (vehicle to ride height) is not recommended
for normal operation. This is a fail safe if the "STORE" button is not used to retract the jacks.
If applicable, the air will dump for thirty (30) seconds before the leveling procedure starts.
The ignition must be in the "ON" or "ACC." position and the park brake must be set to use the system. The "TRAVEL MODE"
light will be on and one or two yellow level indicator lights may be on anytime the ignition is in the "ON" or "ACC" position. The
"NOT IN PARK/ BRAKE" indicator light will come on while the "AUTO LEVEL" button is being pushed if the park brake signal is
not present. The system will not function.
NOTE: If the vehicle is equipped with remote leveling system rocker switches, pushing a rocker switch to "LEVEL"
will start the automatic leveling process. The rocker switch light will flash.
PUMP PROTECTION:
pump off and lock the system if a total of 3 minutes is reached. Example: The pump runs for 1 minute and is off for 20 seconds.
The pump must run 2 minutes and 20 seconds more without interruption to turn the pump off. Any "OFF" time adds more run
time for the pump. This includes operation of HWH rooms. Turn the ignition off, push the "EMERGENCY STOP" button or
release the park brake to "UNLOCK" the system.
CAUTION:
IF THE VEHICLE IS EQUIPPED WITH A PILOT AIR DUMP FOR THE SUSPENSION AND A BUTTON
IS PUSHED TO STOP THE AUTOMATIC LEVELING PROCESS, THE SUSPENSION WILL CONTINUE TO DUMP AIR.
PUSHING THE "STORE" BUTTON OR RELEASING THE PARK BRAKE AFTER THE LEVELING PROCESS IS STOPPED
WILL RETURN THE PILOT AIR DUMP TO THE TRAVEL POSITION.
The HWH system has pump protection built into the control box. An up and down timer will turn the
Any time the ignition is on, the control box will turn the master relay on. The
park brake does not have to be set for the master relay to be on.