TM 1-1520-238-T-4
4–117
4–36.
ENGINE 2 – DOES NOT ACCELERATE TO OR REMAIN BETWEEN 23% AND 25% NG
4–36
IN IGN OVRD
Tools:
Nomenclature
Part Number
Tool Kit, Aircraft
SC518099CLA01
Mechanic’s
Tool Kit, Electrical
SC518099CLA06
Repairer’s
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
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 2 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 fail 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. Perform external power
application – electrical (TM 1-1520-238-23). Set
and hold ENG START NO 2 switch in IGN
OVRD, check for 28 VDC at J22–24.
Is voltage present?
YES
Go to step 5.
NO
Go to step 4.
4. Set and hold ENG START NO 2 switch in IGN
OVRD, check for 28 VDC at P978–B2.
Is voltage present?
YES
Go to step 8.
NO
Go to step 11.
5. Check for open between:
P22–23 and P40–1,
P22–24 and P40–2.
Does open exist?
YES
(ABY) Repair open wire.
Go to paragraph 4–13.
(ABZ) Replace wire harness
(TM 1-1520-238-23).
NO
Go to step 6.
6. Check for open between J22–23 and ground.
Does open exist?
YES
Repair open wire.
Go to paragraph 4–13.
NO
Go to step 7.
7. Have assistant check engine 2 start regulator
valve operation while cycling ENG START NO 2
switch between OFF and IGN OVRD.
Does valve operate?
YES
Replace engine 2 air turbine
starter (TM 1-1520-238-23).
NO
Replace engine 2 starter
regulator valve
(TM 1-1520-238-23).
