SECTION V: TROUBLESHOOTING
TM 9-2350-256-20
WARNING
Remove all jewelry such as rings, dog
tags, bracelets, etc. If jewelry contacts a
metal surface a direct short may result in
instant
heating
of
tools,
damage
to
equipment,
and
injury
or
death
to
personnel.
K
Reconnect wire 487 to 15 A circuit. Disconnect wire
487A from PREHEAT switch side of 15 A circuit
breaker. Place red lead of multimeter in wire 487A and
black lead to ground. Turn MASTER and PREHEAT
switches ON, and check for voltage. Turn MASTER
and PREHEAT switches OFF. If voltage is present,
replace circuit breaker (see paragraph 13-7). If voltage
is not present, go to step L.
L
Reconnect wire 487A to PREHEAT switch side of
circuit breaker. Disconnect wire 487A from
PREHEAT switch. Place red lead of multimeter on
terminal of preheat switch and black lead to ground.
Turn MASTER and PREHEAT switches ON, and check
for voltage. Turn MASTER and PREHEAT switches
OFF. If voltage is present, repair/replace wire 487A of
APU control box wiring harness (see paragraph 13-7).
If voltage is not present, go to step M.
M
Reconnect wire 487A to PREHEAT switch. Disconnect
GND wire from PREHEAT switch. Place red lead of
multimeter in GND wire and black lead to ground.
Turn MASTER and APU GEN switches ON and check
for voltage. Turn MASTER and APU GEN switches
OFF. If voltage is present, replace PREHEAT switch
(see paragraph 13-7). If voltage is not present, replace
GND wire of APU control box wiring harness (see
paragraph 13-7).
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