TM 5-5420-234-14&P
4-12. UNIT TROUBLESHOOTING (continued).
16. MAIN FRAME, HOOK ARM, AND WINCH DO NOT OPERATE (continued).
11.
KNOWN INFO
TEST OPTIONS
Are 2228 volts mea-
Cab control box main
Voltage Test.
sured at the cab con-
power supply OK.
trol box, connector
Cab and remote controls
REASON FOR QUESTION
(J2), position A, with
inoperative.
Whenever a LHS/winch
the joystick in the load
CB15 OK.
function is activated a free
or unload position?
Hydraulic system OK.
flow valve closes to provide
POSSIBLE PROBLEMS
hydraulic pressure to the
CBT. This function is
Cab control box faulty.
controlled by a relay in the
Relay K9 faulty.
cab control box. If there is
Main linking harness
no voltage measured at
faulty.
position A, the free flow
Main junction box wiring
valve will not function.
faulty.
CBT ground circuit faulty.
Free flow valve solenoid
harness faulty.
Free flow valve solenoid
Go to Step 16.
NO
faulty.
YES
4-370
