Stabil-Trak™ Solenoid Valves - JLG sky trak mmv Service Manual

b. Locked Mode (7)
With the boom above 40° and by activating one or more
of the functions (as follows), the Stabil-TRAK™ system is
in the LOCKED MODE and the rear axle is locked so it is
rigid with the frame. The Stabil-TRAK™ light will be ON.
• Engaging the parking brake switch
• Placing the travel select lever in [N] NEUTRAL
• Depressing and holding the service brake pedal
The frame sway control will function slower than normal
in this mode.
Above
LOCKED
40°
MODE
c. Final Positioning Mode (8)
With the boom above 40°, the Stabil-TRAK™ system is
now in the FINAL POSITIONING MODE. In this mode the
rear axle is UNLOCKED and is allowed to pivot, but will re-
spond SLOWLY to changes in terrain. The Stabil-TRAK™
light will be OFF.
The frame sway control function will function normally in
this mode.
To check that the Stabil-TRAK™ System is functioning
properly, refer to "Stabil-TRAK™ System Test" on
page 11.28 for the proper system function.
Above
FINAL
40°
POSITIONING
MODE
Model MMV Rev. 12/04
7
Stabil-TRAK
Light
"ON"
OS14812
8
Stabil-TRAK
Light
"OFF"
OS14922
Stabil-TRAK™ System
11.3.2 Stabil-TRAK™ Solenoid Valves
There are five Stabil-TRAK™ solenoid valves (9) attached
to the Stabil-TRAK™ manifold, attached to the stabilizer
cylinder above the left side of the rear axle.
If a solenoid valve is suspected of malfunctioning, discon-
nect the coil wiring lead and test the coil for proper resis-
tance (7-9 ohms) and for proper voltage from the harness
(12 VDC). Replace the solenoid coil if open or shorted to
ground.
Also inspect the valve cartridge, o-rings, and the other hy-
draulic and electrical components in the circuit to accurately
determine the cause of the problem.
All solenoid cartridge valves 4A (10), 4B (11) , 12A (12)
and 12B (13) are identical and can be interchanged for
diagnostic purposes.
Note: There is an orifice plug beneath each of the
solenoid cartridge valves, 4A (10) and 4B (11). These
plugs must stay in these positions if you interchange the
solenoid cartridge valves.
12
10
11
13
In general, if there is a problem with the Stabil-TRAK™
system beyond common electrical troubles, the involved
electrical and hydraulic circuits should each be checked
and the exact source of the problem diagnosed before
any parts are replaced.
9
MT3130
11.5