CHAPTER 2: VEHICLE MAINTENANCE INSTRUCTIONS
TM 9-2350-256-20
2-19 ELECTRICAL TROUBLESHOOTING-Continued
APU FUEL SOLENOID SYSTEM-Continued
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.
F
Reconnect wire 419 to circuit breaker. Disconnect
wire 419 from APU FUEL SHUTOFF switch side of 15 A
circuit breaker. Place red lead of multimeter on terminal of
circuit breaker and black lead to ground. Turn MASTER
switch on and check for voltage. Turn MASTER switch
OFF. If voltage is present, go to step G. If voltage is not
present, replace 15 A circuit breaker (see paragraph 13-7).
G
Reconnect wire 419 to APU fuel shutoff switch side
of 15 A circuit breaker. Disconnect wire 419 from circuit
breaker side of APU FUEL SHUTOFF switch. Place red
lead of multimeter in wire 419 and black lead to ground.
Turn MASTER switch on and check for voltage. Turn
MASTER switch OFF. If voltage is present, go to step H.
If voltage is not present, repair/replace wire 419 of APU
fuel shutoff switch lead assembly from circuit breaker to
shutoff switch (see paragraph 13-7).
H
Reconnect wire 419 to circuit breaker side of APU
FUEL SHUTOFF switch. Disconnect wire 421 from APU
FUEL SHUTOFF switch. Place red lead of multimeter on
terminal of APU FUEL SHUTOFF switch and black lead to
ground. Turn MASTER and APU FUEL SHUTOFF
switches ON and check for voltage. Turn MASTER and
APU FUEL SHUTOFF switches OFF. If voltage is present,
repair/replace wire 421 of APU control box wiring harness
(see
paragraph 13-7). If voltage is not present, replace APU
FUEL SHUTOFF switch (see paragraph 13-7).
2-172
