CHAPTER 2: VEHICLE MAINTENANCE INSTRUCTIONS
TM 9-2350-256-20
2-19 ELECTRICAL TROUBLESHOOTING--Continued
APU LOW OIL PRESSURE 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 APU control box to foot dimmer switch and
bulkhead wiring harness to APU control box. Remove
four screws (10), four lockwashers (11), and release
rear panel (12) from APU control box. Disconnect wire
419 from panel connector side of 15 A circuit breaker.
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 G. If voltage is not present,
repair/replace wire 419 of APU control box wiring
harness (see paragraph 13-7).
G
Reconnect wire 419 to panel connector side of 15 A
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 H. If voltage is not
present, replace 15 A circuit breaker (see paragraph
13-7).
2-178
