TM 5-5420-234-14&P
4-12. UNIT TROUBLESHOOTING (continued).
15. LHS DOES NOT OPERATE PROPERLY IN AUTO MODE (CAB ONLY)
(continued).
24.
TEST OPTIONS
KNOWN INFO
Voltage Test.
Are 2228 volts mea-
LHS OK using manual
sured on the socket for
controls.
relay K6, position 85?
Hook arm and main frame
REASON FOR QUESTION
unload OK.
The hook arm load function
Main frame loads OK.
is triggered by the closing
Hook arm fails to load.
of relay K6, which is
Main frame down
controlled by a proximity
proximity switch OK.
switch. If voltage is
Main frame junction box
measured at the socket for
wire harness OK.
relay K6, it indicates that
Main LHS harness OK.
the signal voltage from the
Main junction box wiring
proximity switch is reach-
OK.
ing the relay.
Linking harness OK.
POSSIBLE PROBLEMS
Repair cab control
Relay K6 faulty.
NO
box (para 4-71).
Cab control box faulty.
Replace relay K6
YES
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