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
12.
TEST OPTIONS
LHS OK using manual
Is there continuity
Continuity Test.
controls.
measured on the (24-
Hook arm unloads OK.
pin) linking harness
REASON FOR QUESTION
Main frame fails to
between cab control
Supply voltage, signal
unload.
box connector (P2)
voltage, and ground
Hook arm up proximity
and main junction box
circuit are transferred
switch OK.
connector (P4)?
from the cab control box
Main frame junction box
to the main junction box
wire harness OK.
via this harness. Faults
Main LHS harness OK.
in this harness will
Main frame junction box
prevent proper LHS
wire harness OK.
operation.
POSSIBLE PROBLEMS
Linking harness faulty.
Relay K8 faulty.
Replace (24-pin)
Cab control box faulty.
NO
linking harness (para
YES
4-322
