TM 1-1520-238-T-4
4–96
4–18.
ENGINE 2 TORQUE INDICATION IS LOWER THAN ENGINE 1 TORQUE INDICATION
4–18
(INDICATIONS NOT WITHIN 5% OF EACH OTHER)
Tools:
Nomenclature
Part Number
Tool Kit, Electrical
SC518099CLA06
Repairer’s
Multimeter, Digital
AN/PSM-45
Personnel Required:
68F
Aircraft Electrician
References:
TM 1-1520-238-23
TM 55-2840-248-23
Equipment Conditions:
Ref
Condition
TM 1-1520-238-23
Access provisions –
LN3, LN4, RN3, RN4
doors opened
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:
J23–4 and J24–4,
J23–5 and J24–7.
Does open exist?
YES
Repair open wire.
Go to paragraph 4–15.
NO
Go to step 2.
2. Check for open between:
P23–4 and P41–22,
P24–5 and P41–24.
Does open exist?
YES
(ABY)Repair open wire.
Go to paragraph 4–15.
(ABZ) Replace wire harness
(TM 1-1520-238-23).
NO
Go to step 3.
3. Detach P23 and P24. Check for short between:
P23–4 and ground,
P23–5 and ground,
P24–4 and ground,
P24–7 and ground.
Does short exist?
YES
(ABY)Repair shorted wire.
Go to paragraph 4–15.
(ABZ) Replace wire harness
(TM 1-1520-238-23).
NO
Go to step 4.
4. Check for short between:
J23–4 and ground,
J23–5 and ground,
J24–4 and ground,
J24–7 and ground.
Does short exist?
YES
Repair shorted wire between:
J24–4 and P452–A,
J452–A and J23 SP1,
J23 SP1 and P400–46,
J23 SP1 and J24–6,
J24–5 and P452–B,
J452–B and J23 SP3,
J23 SP3 and J23–7.
Go to paragraph 4–15.
NO
Refer to TM 55-2840-248-23 to
troubleshoot engine 2
(ABY) ECU.
(ABZ) DECU.
END OF TASK
