TM 1-1520-238-T-4
4–125
4–43.
ENGINE 2 NG – DOES NOT DECREASE WITH CKT A AND B SWITCHES CLOSED
4–43
Tools:
Nomenclature
Part Number
Tool Kit, Electrical
SC518099CLA06
Repairer’s
Multimeter, Digital
AN/PSM-45
Personnel Required:
68F
Aircraft Electrician
One person to assist
References:
TM 1-1520-238-23
TM 55-2840-248-23
Equipment Conditions:
Ref
Condition
TM 1-1520-238-23
Access provisions –
L140 fairing removed
Paragraph 1–17
Maintenance headset
connected
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. Check for open between:
P22–7 and P42–6,
P22–6 and P42–12,
P22–8 and P42–14.
Does open exist?
YES
(ABY) Repair open wire. Go to
paragraph 4–12.
(ABZ) Replace wire harness
(TM 1-1520-238-23).
NO
Go to step 2.
2. Check for open between:
P22–7 and P175–8,
P22–6 and P175–6,
P22–8 and P175–10.
Does open exist?
YES
Repair open wire.
Go to paragraph 4–13.
NO
Go to step 3.
3. Set and hold CKT A switch in ENG 2 position.
Check for open between (A78):
J1–6 and J1–8.
Does open exist?
YES
Replace pilot EMERG PWR
CHK OVSP TEST panel
(TM 1-1520-238-23).
NO
Go to step 4.
4. Set and hold CKT B switch in ENG 2 position.
Check for open between (A78):
J1–8 and J1–10.
Does open exist?
YES
Replace pilot EMERG PWR
CHK OVSP TEST panel
(TM 1-1520-238-23).
NO
Refer to TM 55-2840-248-23 to
troubleshoot engine 2.
END OF TASK
