TM 5-5420-234-14&P
4-12. UNIT TROUBLESHOOTING (continued).
15. LHS DOES NOT OPERATE PROPERLY IN AUTO MODE (CAB ONLY)
(continued).
22.
TEST OPTIONS
KNOWN INFO
Are 2228 volts mea-
Voltage Test.
LHS OK using manual
sured at main junction
controls.
box terminal strip,
Hook arm and main frame
REASON FOR QUESTION
position 6?
unload OK.
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 junction
proximity switch OK.
box.
Main frame junction box
wire harness OK.
Main LHS harness OK.
POSSIBLE PROBLEMS
Main junction box wiring
Replace main
faulty.
junction box
NO
Linking harness faulty.
harness (para 4-
Relay K6 faulty.
Cab control box faulty.
YES
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