Leveling Jacks; Auto Leveling - JLG 4394RT Operation And Safety Manual

Leveling Jacks

The machine may be equipped with auto leveling jacks with a
manual adjust feature. These leveling jacks are operated
through one switch unlike the traditional four switch system.
The leveling jacks are operated by a bang bang valve.
NOTE: The engine speed will drop when the leveling jacks are
activated.

Auto Leveling

1. With the machine in the stowed position turn the
power on, start machine and depress the leveling jack
selection switch located on the front of the platform
control box.
2. While squeezing the trigger switch on the controller,
move the controller forward.
3. Once the leveling jacks make contact with the ground
surface there will be up to a 5 second delay before the
actual auto leveling begins.
NOTE: Due to varying ground conditions, there may be several
delays between machine level corrections. Be sure ample
time is allowed for all leveling adjustments to be com-
pleted.
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SECTION 3 - MACHINE CONTROLS, INDICATORS AND OPERATION
4. Continue to engage the leveling jacks until the tilt
light stops blinking and is no longer lit.
NOTE: If you receive a 2/5 flash code through the system fault
light at the platform control station the machine is unable
to level. You must reposition and try again.
5. To retract the leveling jacks, depress the leveling jack
selector switch and move the controller backward
until the desired position is obtained.
NOTE: The tilt light serves as an indicator that the machine is
outside the allowable lifting operation. When the
machine reaches a position within level of the specific
market specification, the tilt light will go out. Once the
light is out, the level adjustment of the machine may still
be improved. (Refer to Section , Manual Level Adjustment
(Trim)).
NOTE: There is a limit switch that senses when all four cylinders
are fully retracted and this will light up the four leveling
jack lights in the platform control station.
The proximity switch and elevation sensor will not allow
the jacks to be extended or retracted when the platform is
above the stowed position. If there is a proximity switch
failure or elevation sensor failure, the leveling jacks func-
tion is locked out.
– JLG Lift – 3-19