TM 9-4940-568-20
2-160
Table 2-21. Crane Troubleshooting (CONT).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
7. BOOM DOES NOT TELESCOPE IN WITH REMOTE CONTROL.
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.
Test 1.
Loosen screw and remove connector from telescope IN solenoid. Place
EMERGENCY STOP switch in ON position. Hold remote control unit telescope
controller in IN position and check for 24 volts between solenoid connector, terminal
1, and known good ground.
If 24 volts are not present, go to Test 2.
If 24 volts are present, turn MAIN POWER switch OFF and go to Test 8.
Test 2.
Disconnect the remote control cable from the remote control unit and remote control
hook-up connector on crane sub-frame. Check the cable for continuity between the
two cable ends, terminal D.
If no continuity is found on terminal D, replace the remote control cable.
If continuity is found, go to Test 3.
