W DOC AIRBUS | TSM A320F

DMU Inoperative

TASK 31-36-00-810-801-A
DMU Inoperative

1. Possible Causes
  • DMU [1TV]
  • wiring
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
ASM 313403
AMM 31-36-00-710-001
Test of the DMU
AMM 31-36-00-710-004
AIDS Software Load Procedure
ASM 313601
AMM 31-36-34-000-001
Removal of the Data Management Unit (DMU)
AMM 31-36-34-400-001
Installation of the Data Management Unit (DMU)
3. Fault Confirmation
Subtask 31-36-00-740-050-B ** ON A/C NOT FOR ALL
A. Do the DMU (1TV) fault monitoring test AMM 31-36-00-710-001.
   (1) If the result power up test page gives the following messages, replace the DMU [1TV] AMM 31-36-34-000-001 and AMM 31-36-34-400-001:

  • EPROM I/O FAILURE (CPU1). . . . . . . . I . . .2
  • SRAM FAILURE (CPU1). . . . . . . . . . .I . . .2
  • FLASH PROM FAIL (CPU1). . . . . . . . . I . . .2
  • ACQUI. BUS INTERFACE. . . . . . . . . . I . . .2
  • DIAL. BUS INTERFACE. . . . . . . . . . .I . . .2
  • EEPROM FAILURE (CPU1). . . . . . . . . .I . . .2
  • INVALID OP SOFT. . . . . . . . . . . . .I . . .2
  • CPU1/CPU2 SYNCHRO. . . . . . . . . . . .I . . .2
  • EPROM FAILURE (CPU2). . . . . . . . . . I . . .2
  • SRAM FAILURE (CPU2). . . . . . . . . . .I . . .2
  • FLASH PROM FAIL (CPU2). . . . . . . . . I . . .2
  • SAR MEMORY FAILURE. . . . . . . . . . . I . . .2
  • DAR EMISSION FAILUR. . . . . . . . . . .I . . .2
  • CPU1/CPU2 SYNC. FAILURE. . . . . . . . .I . . .2
  • POWER SUPPLY ALARM. . . . . . . . . . . I . . .2
  • INVALID OP. SOFTWARE. . . . . . . . . . I . . .3
  • INVALID DATABASE. . . . . . . . . . . . I . . .3
4. Fault Isolation
Subtask 31-36-00-810-050-A ** ON A/C NOT FOR ALL
A. If the DMU (1TV) test gives the maintenance message DMU only:
  • make sure that the CB 4TV is closed,
  • do a check for 115 VAC at the DMU (1TV) connectors AC/1 and AC/7 ASM 313601.
   (1) If there is 115 VAC:
   (2) If the fault continues:
  • do a check of the correct FDIU engine pin programming ASM 313403.

   (3) If the fault continues:
  • do a check and repair the wiring as necessary ASM 313601, between:

    DMU (1TV) Ground pin AA/15J and ground,

    DMU (1TV) Ground pin AA/15K and ground,

    DMU (1TV) Ground pin AB/15J and ground,

    DMU (1TV) Ground pin AB/15K and ground.
Subtask 31-36-00-810-145-A ** ON A/C NOT FOR ALL
B. If the DMU (1TV) test gives the maintenance message DMU only:
  • make sure that there is no difference between the software and the A/C configuration
  • interchange the EVMU with an EVMU with a different P/N.
   (1) If the fault continues:
  • load again the DMU software through floppy only AMM 31-36-00-710-004, use the media disks supplied by the vendor (refer to IPC).
Subtask 31-36-00-740-053-A ** ON A/C NOT FOR ALL
C. Do the test given in paragraph 3.A. again to check the correct operation
(no maintenance message display).
[Rev.8 from Aug 2018] 2026.04.04 04:40:06 UTC
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