TM 1-1520-238-T-4
4–107
4–26.
ENGINE 1 NG – DOES NOT DECREASE WITH CKT A AND CKT B SWITCHES
4–26
CLOSED
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 –
L230 fairing removed
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:
P21–7 and P41–6,
P21–6 and P41–12,
P21–8 and P41–14.
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:
J21–7 and P175–7,
J21–6 and P175–5,
J21–8 and P175–9.
Does open exist?
YES
Repair open wire.
Go to paragraph 4–12.
NO
Go to step 3.
3. Have assistant set and hold CKT A switch in
ENG NO 1 position. Check for open between
(A78): J1–5 and J1–7.
Does open exist?
YES
Replace pilot EMERG PWR
CHK OVSP TEST panel
(TM 1-1520-238-23).
NO
Go to step 4.
4. Have assistant set and hold CKT B switch in
ENG NO 2 position. Check for open between
(A78): J1–7 and J1–9.
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 1.
END OF TASK
