Genie GTH-636 Service Manual page 158

Section 5 • Troubleshooting
TROUBLESHOOTING
Fork Rotate Function
Symptom:
Fork rotates in one direction only (if equipped).
1 Turn the key switch to the on position. Start the
engine.
2 Operate the manual over ride at both ends of
the fork rotate valve.
Result: The machine functions correctly.
Proceed to step 3.
Result: The machine does not function
correctly. Remove air from the fork rotate
circuit. Refer to Repair Procedure 1-6, How to
Replace the Fork Rotate Cylinder Hoses.
3 Troubleshoot the fork rotate electrical circuit.
While activating the fork rotate function in one
direction, use a wrench to check for magnetism
in the solenoid valve of the fork rotate manifold.
Touch a wrench to the valve.
Result: The wrench sticks to the valve. The coil
is good.
Result: The wrench does not stick to the valve.
Repair or replace the wire circuit from the fork
tilt switch to the fork tilt valve coil OR replace
the fork tilt switch OR replace the valve coil.
Note: A fast way to determine if a valve coil is
functioning correctly is to touch a wrench to the
end of the valve when the coil is activated. When
energized, the valve will magnetize and the wrench
will stick to the valve; turn the power off and the
wrench will fall.
5 - 10 GTH-636 • GTH-644 • GTH-842 • GTH-844 • GTH-1048 • GTH-1056
4 Activate the fork rotate switch in the opposite
direction from step 3 and use a wrench to
check for magnetism in the solenoid valve of
the fork rotate manifold. Touch a wrench to the
valve.
Result: The wrench sticks to the valve. The coil
is good. Replace the valve (schematic item LA).
Result: The wrench does not stick to the valve.
Repair or replace the wire circuit from the fork
tilt switch to the fork tilt valve coil OR replace
the fork tilt switch OR replace the valve coil.
June 2007
REV B
Part No. 97487