TM 9-4940-568-20
2-204
Table 2-21. Crane Troubleshooting (CONT).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
4. HOIST DOES NOT OPERATE.
NOTE
Before performing crane troubleshooting procedures, make sure the FRS electrical
supply system is functioning properly.
Unless advised otherwise, the FRS 24V MASTER switch and the crane MAIN
POWER switch must be in the ON position for all voltage checks.
This malfunction applies when both the remote control and manual control operations
are affected.
Test 1.
Are tubes, hoses and fittings between the HOIST manual control valve and hoist
hydraulic motor manifold free of damage, crimps or leaks?
If leaks or damaged lines are found, repair as needed. Refer to paragraph 7-4 in
this manual.
If no leaks or damage are found, go to Test 2.
Test 2.
Are the hoses and fittings between the hoist hydraulic motor manifold and the hoist
brake free of damage, crimps or leaks?
If leaks or damaged lines are found, repair as needed. Refer to paragraph 7-4 in
this manual.
If no leaks or damage are found, go to Test 3.
Test 3.
Are the hoses and fittings between the hoist brake and the return drain fitting free of
damage, crimps or leaks?
If leaks or damaged lines are found, repair as needed. Refer to paragraph 7-4 in
this manual.
If no leaks or damage are found, Notify Supervisor.
END OF TEST
