CHAPTER 2: VEHICLE MAINTENANCE INSTRUCTIONS
TM 9-2350-256-20
2-19 ELECTRICAL TROUBLESHOOTING--Continued
APU GENERATOR SYSTEM (SINGLE VOLTAGE)-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.
G Reconnect engine generator relays to voltage regulator
wiring harness to switching box relay. Disconnect
bulkhead to APU, master relay, and rigger's lights wiring
harness at switching box relay. Place red lead of
multimeter in socket C of wire 61. Turn MASTER and
APU GEN switches ON, start APU, and check for
voltage. Turn APU and MASTER and APU GEN
switches OFF. If voltage is not present, replace
switching relay box (see paragraph 6-13). If voltage is
present, go to step H.
H Place red lead on pin B of wire 478A. Turn MASTER
and APU GEN switches ON, start APU, and check for
voltage. Turn APU and MASTER and APU GEN
switches OFF. If voltage is not present, replace
switching relay box (see paragraph 6-13). If voltage is
present, go to step I.
I Reconnect bulkhead to APU, master relay, and rigger's
lights wiring harness to switching box relay. Open front
grille doors (TM 9-2350-256-10). Disconnect bulkhead
to APU, master relay, and rigger's lights wiring harness
from APU engine disconnect. Place red lead of
multimeter on pin H of wire 478A. Turn MASTER and
APU GEN switches ON and check for voltage. Turn
MASTER and APU GEN switches OFF. If voltage is not
present, repair/replace wire 478A of bulkhead to APU,
master relay, and rigger's lights wiring harness (see
paragraph 6-76). If voltage is present, go to step J.
2-150
