TM 1-1520-238-T-6
9–573
9–280. ENG INST CIRCUIT BREAKER (CB17) – DOES NOT STAY CLOSED OR 28 VDC IS NOT
9–280
PRESENT AT (A76): J1-L AND J1-M
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 1-1520-238-23
TM 1-1520-238-T-5
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 ENG INST circuit breaker (CB17) stay
closed?
YES
Go to step 4.
NO
Go to step 2.
2. On pilot center circuit breaker panel, open ENG
INST circuit breaker (CB17). Set BATT/EXT
PWR switch to OFF. Check for short between
(A76)J1-L and ground.
Does short exist?
YES
Go to step 3.
NO
Refer to TM 1-1520-238-T-5 to
troubleshoot engine
instruments.
3. Detach wire at CB17-2. Check for short between
(A76)J1-L and ground.
Does short exist?
YES
Repair shorted wire.
Go to paragraph 9–263.
NO
Replace ENG INST circuit
breaker (CB17)
(TM 1-1520-238-23).
4. Set BATT/EXT PWR switch to OFF. Check for
open between:
CB17-2 and (A76)J1-L,
CB17-2 and (A76)J1-M.
Does open exist?
YES
Repair open wire.
Go to paragraph 9–263.
NO
Replace ENG INST circuit
breaker (CB17)
(TM 1-1520-238-23).
END OF TASK
