TM 1-1520-238-T-6
9–438
9–188. IHADSS CIRCUIT BREAKER (CB1) – DOES NOT STAY CLOSED OR 115 VAC IS
9–188
NOT PRESENT AT: P1-E, P1-D, P1-C
Tools:
Nomenclature
Part Number
Tool Kit, Electrical
SC518099CLA06
Repairer’s
Multimeter, Digital
AN/PSM-45
Personnel Required:
References:
TM 1-1520-238-23
TM 9-1270-221-23
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 IHADSS circuit breaker (CB1) stay
closed.
YES
Go to step 2.
NO
Go to step 3.
2. Set BATT/EXT PWR switch to OFF. Check for
open between:
CB1-A1 and CB3-A1,
CB1-B1 and CB3-B1,
CB1-C1 and CB3-C1,
CB1-A2 and P1-E,
CB1-B2 and P1-D,
CB1-C2 and P1-C.
Does open exist?
YES
Repair open wire.
Go to paragraph 9–172.
NO
Replace IHADSS circuit breaker
(CB1) (TM 1-1520-238-23).
3. Open CB1 and set BATT/EXT PWR switch to
OFF. Check for short between:
P1-C and ground,
P1-D and ground,
P1-E and ground.
Does short exist?
YES
Go to step 4.
NO
Refer to TM 9-1270-221-23 to
troubleshoot IHADSS.
4. Detach wire at CB4-A2, CB4-B2, CB4-C2.
Check for short between:
P1-C and ground,
P1-D and ground,
P1-E and ground.
Does short exist?
YES
Repair shorted wire.
Go to paragraph 9–172.
NO
Replace IHADSS circuit breaker
(CB1) (TM 1-1520-238-23).
END OF TASK
