TM 5-5420-234-14&P
4-12. UNIT TROUBLESHOOTING (continued).
15. LHS DOES NOT OPERATE PROPERLY IN AUTO MODE (CAB ONLY)
(continued).
KNOWN INFO
21.
TEST OPTIONS
Continuity Test.
LHS OK using manual
Is there continuity
controls.
measured on the main
REASON FOR QUESTION
Hook arm and main
LHS wire harness,
frame unload OK.
between the main
The hook arm down
Hook arm fails to load.
frame junction box
proximity switch signal is
Main frame down
harness connector (P6)
transferred from the main
proximity switch OK.
and connector (P7)?
frame junction box to the
Main frame junction box
main frame junction box
harness OK.
via this harness. Faults
in this harness will
POSSIBLE PROBLEMS
prevent AUTO operation.
Main LHS harness faulty.
Main frame junction box
harness faulty.
Replace main LHS
Linking harness faulty.
wiring harness
NO
Relay K6 faulty.
Cab control box faulty.
YES
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