TM 9-4940-568-20
2-155
Table 2-21. Crane Troubleshooting (CONT).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Test 6.
Tag and mark connectors on boom controller switches. Remove the connectors
from the two controller switches. Check each switch for continuity between the
following switch terminal locations, with the controller lever in the position noted:
Switch Terminals:
Controller handle position:
Test results:
Check 1
NC to COM
Neutral
Continuity
Check 2
NO to COM
Neutral
No continuity (open)
Check 3
NC to COM
Full UP position
No continuity (open)
Check 4
NO to COM
Full UP position
Continuity
If the above test results are not obtained, replace switch(es). Refer to paragraph
5-12 in this manual.
