TM 1–1520–238–T–3
Change 5
29–1
CHAPTER 29
COMPUTER DISPLAY UNIT (CDU) (ADD)
MULTIPLEX READ CODES
FAILURE SYMPTOM INDEX
Symptom
Refer to paragraph
CDU NO–GO MESSAGE DISPLAYED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29–1
Personnel Required:
(2)
References:
TM 9–1230–476–20–2
TM 11–1520–238–23–1
TM 11–1520–238–23–2
Equipment Conditions:
Ref
Condition
TM 11–1520–238–23–2
Doppler – (ADD)
MAINTENANCE
OPERATIONAL CHECK in
progress
TM 9–1230–476–20–2
MULTIPLEX SUBSYSTEM
– POWER UP completed
NOTE
All multiplex read code responses are read from right to
left.
Multiplex read codes must be used in conjunction with
applicable Maintenance Operational Check (MOC) in
progress.
MULTIPLEX READ CODE INTERPRETATIONS
29–1 SIGNAL NAME:
MESSAGE ERROR
MEMORY LOCATION: 002254
MEMORY DATA BIT(S):
9
(BINARY)
CONDITION:
(None)
SIGNAL FUNCTION:
Indicates message error.
REMARKS: From CDU to FCC.
PASS:
If fourth digit displayed on CDU is 0, 1, 4, or 5, go to paragraph 29–2.
FAIL: Location of fault: replace CDU (TM 11–1520–238–23–1).
29–2 SIGNAL NAME:
RESERVED
MEMORY LOCATION: 002254
MEMORY DATA BIT(S):
12-14
(BINARY)
CONDITION:
(None)
SIGNAL FUNCTION:
Indicates serial digital error.
REMARKS: From CDU to FCC.
PASS:
If second and third digits displayed on CDU are 0, go to paragraph 29–3.
FAIL: Location of fault: replace CDU (TM 11–1520–238–23–1).
