TM 1-1520-238-T-6
9–521
9–245. ECS BLADE DE-ICE CIRCUIT BREAKER (CB85) – DOES NOT STAY CLOSED OR 28
9–245
VDC IS NOT PRESENT AT P1-53
Tools:
Nomenclature
Part Number
Tool Kit, Electrical
SC518099CLA06
Repairer’s
Multimeter, Digital
AN/PSM-45
Personnel Required:
68X
Armament/Electrical Systems Repairer
One person to assist
References:
TM 1-1520-238-T-8
TM 1-1520-238-23
WARNING
Turn off power before detaching or
attaching wires and connectors. High
current 28 VDC or 115 VAC is present.
Failure to do so could result in death or
serious injury.
1. On pilot ELEC PWR panel, set BATT/EXT PWR
switch to EXT PWR.
Does ECS BLADE DE-ICE circuit breaker
(CB85) stay closed?
YES
Go to step 4.
NO
Go to step 2.
2. Open CB85. Set BATT/EXT PWR switch to OFF.
Check for short between P1-53 and ground.
Does short exist?
YES
Go to step 3.
NO
Refer to TM 1-1520-238-T-8 to
troubleshoot rotor blade de-ice
system.
3. Detach wire at CB85-2. Check for short between
P1-53 and ground.
Does short exist?
YES
Repair shorted wire between
CB85-2 and P1-53.
Go to paragraph 9–233.
NO
Replace ECS BLADE DE-ICE
circuit breaker (CB85)
(TM 1-1520-238-23).
4. Set BATT/EXT PWR switch to OFF. Check for
open between CB68-1 and P1-53.
Does open exist?
YES
Go to step 5.
NO
Replace ECS BLADE DE-ICE
circuit breaker (CB85)
(TM 1-1520-238-23).
5. Check for open between CB85-2 and P1-53.
Does open exist?
YES
Repair open wire.
Go to paragraph 9–233.
NO
Replace bus bar between CB85
and CB68, check for foreign
material
(TM 1-1520-238-23).
END OF TASK
