REPAIR STEPS
SOLUTION
DIAGRAMS
PROBLEM
MI91.2142
17APR98
REFER TO MP65.3462
If the jack does not retract, unplug the solenoid valve for that jack.
With the panel on, check for power between the 2 pins of the harness
plug for that jack. If power is present, the harness wire is shorted to
ground or the control panel is bad. If power is not present, replace the
solenoid valve.
GREEN
BLUE
BROWN
ORANGE
BA
BA
BA
BA
Part 5 continued
REFER TO MP65.3455
REFER TO MP85.3300
c. The pump runs
under load. A jack
will not extend.
Check the fuse or breaker for that solenoid valve at the fuse (breaker)
panel. Check that there is +12 power on the main stud and the con-
nection terminals at the fuse (breaker) panel. If the fuse is blown,
unplug the valve that will not extend. Two valves will be connected
to each fuse (breaker). Replace the fuse or let the breaker reset. With
the system ON, if the fuse blows or breaker trips, replace the solenoid
valve that is connected to that fuse (breaker). If the fuse does not blow,
plug the unplugged valve back in. If the fuse blows, replace that sol-
enoid valve.
If the fuse is not blown, unplug the solenoid valve for the jack that
will not extend. While pushing the jack control switch to EXTEND, check
for power between the two pins of the harness plug. If power is not
present, the problem is the harness or the control panel. If power is
present, replace the solenoid valve.
d. More than one
jack extends when
a jack control switch
is pushed to "EX-
TEND".
If the system has kick-down jacks the problem is a short in the con-
trol harness or the control panel needs to be rebuilt.
If the system has kick-down or straight-acting jacks and all four
jacks extend,
switches are used, replace the check valve for the jack that lets all four
extend.
If the system has straight-acting jacks,
es. If the same jack extends no matter which switch is pushed,
replace the solenoid valve.
NOTE: The wire for that valve in the con-
trol harness could be shorted to ground. Check for power between
the two pins in the plug for that valve while pushing another switch to
extend. If power is present, the wire is shorted. If not, replace the
solenoid valve.
If only one switch runs two jacks, the control panel should be repair-
ed.
REFER TO MP85.3462
when one switch is pushed but not when other control
e. A jack will not
stay extended when
the switch is re-
leased.
While pushing the jack control switch to EXTEND, push the MASTER
switch to "OFF". If the jack retracts, the problem is either the sol-
enoid valve or the check valve. Replace the solenoid valve. If that
does not fix the problem replace the check valve.
REFER TO MP65.3455
try all four jack control switch-
GREEN
BLUE
BROWN
ORANGE
BA
BA
BA
BA
STAB.
LEFT
REAR
+
H/V
RIGHT
FRONT
FRONT
LEFT
RIGHT
REAR
+
+
+
VALVE
SHUTTLE
CHECK
VALVES (4)
FRONT
+
CHECK
VALVES (4)
REAR
LEFT
STAB.
LEFT
+
+
VALVE
SHUTTLE
H/V
FRONT
RIGHT
+
REAR
RIGHT
A
B
A
B
B A
B A
B A
B A
A
B
GRAY
RED
RIGHT
REAR *
RIGHT
FRONT *
LEFT
FRONT
LEFT
REAR *
HORIZONTAL /
VERTICAL
STABILIZE
ORANGE
GREEN
BLUE
BROWN
YELLOW
PURPLE
RED
RED
RED
RED
RED
RED
RED
#10 BLACK
RED
GRAY
TO PUMP
*
*
*
MAIN STUD
GROUND WIRE
