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
19.
TEST OPTIONS
LHS OK using manual
Are 2228 volts mea-
Voltage Test.
controls.
sured at main frame
Hook arm and main frame
junction box terminal
REASON FOR QUESTION
unload OK.
strip, position 1?
To verify if signal voltage
Main frame loads OK.
from the main frame down
Hook arm fails to load.
proximity switch is
Main frame down
reaching the main frame
proximity switch OK.
junction box.
Main frame down
proximity switch LED on.
POSSIBLE PROBLEMS
Main frame down
proximity switch faulty.
Replace main
Main frame junction box
frame down
harness faulty.
NO
proximity switch
Main LHS harness faulty.
Main junction box wiring
faulty.
Linking harness faulty.
Relay K6 faulty.
YES
Cab control box faulty.
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