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.
I Reconnect wire 421 to APU FUEL SHUTOFF switch.
Disconnect wire 420B from ENGINE OIL PRESSURE
gage. Place red lead of multimeter in wire 420B 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, go to step J. If voltage is not present,
repair/replace wire 421/420B of APU control box wiring
harness (see paragraph 13-7).
J Reconnect wire 420B to ENGINE OIL PRESSURE gage.
Disconnect wire 420 from ENGINE OIL PRESSURE
gage. Place red lead of multimeter on terminal of gage
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 420 of APU control
box wiring harness (see paragraph 13-7). If voltage is
not present, replace ENGINE OIL PRESSURE gage (see
paragraph 13-7).
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