TM 1-1520-238-T-7
10–112
Change 5
10–22. FUEL XFEED CIRCUIT BREAKER – DOES NOT STAY CLOSED (ADA)
10–22
Tools:
Nomenclature
Part Number
Tool Kit, Electrical
SC518099CLA06
Repairer’s
Multimeter, Digital
AN/PSM-45
Personnel Required:
68X
Armament/Electrical Systems Repairer
One person to assist
References:
TM 1-1520-238-T-6
TM 1-1520-238-23
Equipment Conditions:
Ref
Condition
TM 1-1520-238-23
Electrical power
distribution box cover
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. Open FUEL XFEED circuit breaker. Check for
short between ground and P1-32.
Does short exist?
YES
Refer to TM 1-1520-238-T-6 to
troubleshoot circuit protection
system (dc emergency bus –
pilot station).
NO
Go to step 2.
2. Tag and detach wire from (A402): TB3-4-J,
TB3-4-K, TB3-4-L, and TB3-4-M. Check for short
between (A402):
J5-B8 and ground,
J23-B14 and ground,
J1-32 and ground,
J24-B11 and ground.
Does short exist?
YES
Repair shorted wire between
(A402):
J5-B8 and TB3-4-J,
J23-B14 and TB3-4-K,
J1-32 and TB3-4-L,
J24-B11 and TB3-4-M.
Go to paragraph 10–17.
NO
Go to step 3.
3. Check for short between P441-B11 and ground.
Does short exist?
YES
Go to step 6.
NO
Go to step 4.
4. Check for short between P442-B8 and ground.
Does short exist?
YES
Go to step 5.
NO
Go to step 7.
5. Detach P939. Check for short between P442-B8
and ground.
Does short exist?
YES
Repair shorted wire between
P442-B8 and P939-8.
Go to paragraph 10–17.
NO
Replace engine 2 fuel
crossfeed/shutoff valve
(TM 1-1520-238-23).
