TM 1–1520–238–T–3
10–4
Change 4
10–9 SIGNAL NAME:
PNVS SYSTEM STATUS
MEMORY LOCATION: 001136
MEMORY DATA BIT(S):
19
(BINARY)
CONDITION:
(None)
SIGNAL FUNCTION:
Indicates some part of PNVS system has failed.
REMARKS: From TEU through LH FAB MRTU Type I to FCC.
PASS:
If first digit on HOD is 0, 2, 4, or 6, go to paragraph 10–14.
FAIL: Location of fault: set DEK to FD/LS and go to next failure symptom message paragraph; if no
FD/LS message appears, perform maintenance FD/LS (TM 1–1520–238–T–1) and refer to next
failure symptom message paragraph.
10–10 SIGNAL NAME:
BIT ID TO TEU (ACY) BIT ID CMD (ACZ)
MEMORY LOCATION: 001246
MEMORY DATA BIT(S):
5
(BINARY)
CONDITION:
If fifth digit displayed on HOD is 0, 1, 2, or 3=TADS
If fifth digit displayed on HOD is 4, 5, 6, or 7=PNVS
SIGNAL FUNCTION:
Indicates either TADS or PNVS built–in–test (BIT).
REMARKS: From FCC through LH FAB MRTU Type I to TEU.
PASS:
If fifth digit on HOD is 4, 5, 6, or 7, go to paragraph 10–14.
FAIL: Location of fault: LH FAB MRTU Type I, wiring from LH FAB MRTU Type I to TEU, TEU.
Troubleshoot wiring to isolate fault (TM 1–5855–265–T).
10–11 SIGNAL NAME:
PNVS SERVO STATUS
MEMORY LOCATION: 001136
MEMORY DATA BIT(S):
17
(BINARY)
CONDITION:
(None)
SIGNAL FUNCTION:
Indicates servo subsystem has failed.
REMARKS: From TEU through LH FAB MRTU Type I to FCC.
PASS:
Location of fault if first digit on HOD is 4, 5, 6, or 7: LH FAB MRTU Type I, wiring from LH FAB
MRTU Type I to TEU, TEU. Troubleshoot wiring to isolate fault (TM 1–1270–476–T).
FAIL: Location of fault: servo amplifier, wiring from servo amplifier to TEU,TEU, wiring from TEU to
LH FAB MRTU Type I, LH FAB MRTU Type I. Troubleshoot wiring to isolate fault
(TM 1–5855–265–T).
10–12 SIGNAL NAME:
PNVS VIDEO STATUS
MEMORY LOCATION: 001136
MEMORY DATA BIT(S):
18
(BINARY)
CONDITION:
(None)
SIGNAL FUNCTION:
Indicates PNVS video has failed.
REMARKS: From TEU through LH FAB MRTU Type I to FCC.
PASS:
Location of fault if first digit on HOD is 2, 3, 6, or 7: FCC, symbol generator, wiring from
symbol generator to VDU. Troubleshoot wiring to isolate fault (TM 1–1270–476–T).
FAIL: Location of fault: PEU, wiring from PEU to TEU, TEU, wiring from TEU to LH FAB MRTU Type
I, LH FAB MRTU Type I. Troubleshoot wiring to isolate fault (TM 1–1270–476–T).
