Gradall 534B (9020-7317) Service Manual - Manual (Page 134)

PROBLEM PROBABLE CAUSE REMEDY
LOSS OF ELECTRIC Wire loose or broken on first
SIGNAL TO gear pressure switch ...........................................Repair
CONTROLLER
WHEN IN FIRST
Wire loose or broken at diode................................ Repair
First gear pressure switch faulty............................Replace
Diode faulty .......................................................... Replace
Low transmission first gear
clutch pressure ................................................... Check fluid level, check linkage, make sure spool
is shifted properly, check Clark service manual.
Check and clean suction screen.
LOSS OF ELECTRIC Wire loose or broken on second gear
SIGNAL TO pressure switch ...................................................Repair
CONTROLLER
WHEN IN SECOND
Wire loose or broken at diode.................................Repair
Second gear pressure switch faulty........................ Replace
Diode faulty Replace............................................. Replace
Low transmission second gear
clutch pressure ................................................... Check fluid level, check linkage, make sure spool
is shifted properly, check Clark service manual.
Check and clean suction screen.
SERIES/PARALLEL Drain from series/parallel solenoid
VALVE NOT valves blocked or restricted ........................ Check lines, clean or replace.
RETURNING TO
NEUTRAL IN
Series/parallel solenoid valve spool
THIRD GREAR sticking in “On” position ....................................Check solenoid and wiring.
Faulty series/parallel valve
(Sticky or broken spring) ................................... Repair, check plunger. Replace springand O-Rings.
LOSS OF ELECTRIC Wire loose at diode ............................................... Repair
SIGNAL TO Wire loose at controller ......................................... Repair
CONTROLLER IN
FIRST & SECOND
Wire loose at controller ......................................... Repair
LOW PILOT Wire loose at first and second
PRESSURE pressure switches............................................... Repair
CONTROLLER Low Pilot Pressure.................................................Reset, 350 psi
STUCK
Diode faulty ...........................................................Replace
Both first and second pressure
switches faulty ...................................................Replace
Controller stuck .....................................................Check pilot pressure. Repair valve.
REAR WHEEL SKID (LOCK UP)
OR ROTATE VERY SLOWLY
2