TM 10-5410-228-24
2.8
UNIT LEVEL TROUBLESHOOTING PROCEDURES Continued.
7.
NO AIR FLOW WHEN MISSION PROFILE SWITCH IS SET FOR STATIC MODE EXTERNAL
POWER `STATIC' INDICATOR ON, NBC SWITCH OFF, EXTERNAL HYDRAULIC PUMP
INDICATOR ON.
Gain access to ECU front covers while system is running.
Set ESS MODE switch to VENT.
Turn override button on solenoid valve SV2
counterclockwise to open. (see para 2.14.4).
Check for rotation of NBC fan and recirculation fan.
Does
No
AC motor
start?
Yes
Does
No
NBC fan
rotate?
Yes
Does
No
recirculation
Push in override on SV9.
fan rotate?
Yes
Does
No
Check shaft
recirculation
Remove electrical connector plug from SV2.
coupling.
fan rotate?
Test for 24 Vdc across connector plug pins.
Is
Yes
24 Vdc
Yes
Replace SV2.
present?
Remove connector plug
from SV9.
Test for 24 Vdc across
No
connector plug pins.
Is
No
Yes
24 Vdc
Replace SV9.
present?
1
3
2
