TM 1-1520-238-T-4
497
419.
ENGINE 1 DOES NOT ACCELERATE TO OR REMAIN BETWEEN 23% AND 25% NG
419
IN IGN OVRD
Tools:
Nomenclature
Part Number
Tool Kit, Aircraft
SC518099CLA01
Mechanics
Tool Kit, Electrical
SC518099CLA06
Repairers
Multimeter, Digital
AN/PSM-45
Personnel Required:
67R
Attack Helicopter Repairer
68F
Aircraft Electrician
References:
TM 1-1520-238-T-5
TM 1-1520-238-T-6
TM 1-1520-238-23
Equipment Conditions:
Ref
Condition
TM 1-1520-238-23
Access provisions
RN1 door opened
Paragraph 117
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 PAS manifold and engine 1 starter
regulator valve lines for leaks.
Are leaks present?
YES
Replace leaking components
(TM 1-1520-238-23).
NO
Go to step 2.
2. Start and operate APU (TM 1-1520-238-23). On
pilot caution/warning panel check SHAFT
DRIVEN COMP indicator.
Is SHAFT DRIVEN COMP fail indicator
lighted?
YES
Refer to TM 1-1520-238-T-5 to
troubleshoot PAS.
NO
Go to step 3.
3. Shutdown APU, then perform external power
application electrical (TM 1-1520-238-23). Set
and hold ENG START NO 1 switch in IGN
OVRD, check for 28 VDC at J2124.
Is voltage present?
YES
Go to step 5.
NO
Go to step 4.
4. Set and hold ENG START NO 1 switch in IGN
OVRD, check for 28 VDC at P977B2.
Is voltage present?
YES
Go to step 8.
NO
Go to step 11.
5. Check for open between:
P2124 and P392,
P2123 and P391.
Does open exist?
YES
(ABY) Repair open wire.
Go to paragraph 412.
(ABZ) Replace wire harness
(TM 1-1520-238-23).
NO
Go to step 6.
6. Check for open between:
(AAG) J2123 and ground,
(ABC) J2123 and ground.
Does open exist?
YES
Repair open wire.
Go to paragraph 412.
NO
Go to step 7.
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