TM 9--2350--292--20--1
0018 00--18
AUXILIARY POWER UNIT FAILS TO CRANK -- CONTINUED
0018 00
CONTINUED FROM STEP AM
no
yes
AN
Replace START switch
(WP 0247 00). Verify
fault is corrected.
no
yes
AO
Repair (WP 0290 00) or
replace (WP 0247 00)
harness 4W725. Verify
fault is corrected.
Is continuity present?
Is continuity present?
1. Reconnect lead 4W123--5 to circuit breaker
CB1 connector.
2. Disconnect lead 65 from START switch
connector.
3. Place multimeter leads across START
switch connectors and turn switch to MOM
ON.
4. Check for continuity.
1. Place multimeter red lead onto 4W725 pin D
and black lead to lead 65.
2. Check for continuity.
3. Reconnect lead 65 to START switch
connector.
AP
If APU still fails to crank, go to (WP 0021 00).
END OF TASK
