31-31-03
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757
MAINTENANCE MANUAL
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| | | | IS | |
| | | | Front | |
| | | IS | Panel | |
| DFDAU | | FRCP | DFDAU | |
| Bite | | Light | BITE | Action |
| Code | Bite Code Description | ON? |LED ON? | Note |
................................................................................ |445 |FMC unknown DMU database command | NO | NO |Note 4 | 2........…..........................................…........…........…........1
~........................................................... | Acronyms And Abbreviations | ............................................................. | AIC |Analog Interface Card | | DB |Database | | DFDAU |Digital Flight Data Acquisition Unit | | DFDR |Digital Flight Data Recorder | | DIC |Digital Interface Card | | DMU |Data Management Unit | | FMC |FDAU Master Controller | 2..............…............................................1
ú
31-31-03
ALL ú ú 02 Page 407 ú Jan 20/98
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757
MAINTENANCE MANUAL
~.............................................................................. | MAINTENANCE ACTION NOTES | ................................................................................ |Note 1: |This fault can occur if the +28VDC accelerometer excitation (LMP14E)| | |is grounded. Check accelerometer before removing the DFDAU unit. | ................................................................................ |Note 2: |This fault can occur if the +5VDC potentiometer excitation (RMP14E) |
| |is grounded. Check if the analog potentiometer excitation is |
| |grounded outside the DFDAU unit before removing and replacing the |
| |unit. |
................................................................................ |Note 3: |This fault can occur if any of the analog inputs to the DFDAU unit | | |are out of range or a leg on a three or four leg analog is missing. | | |The unit should not be returned until the analog input port is | | |checked. | ................................................................................ |Note 4: |The DFDAU unit requires databases for each airframe. These | | |databases are preloaded by AlliedSignal prior to unit shipping. | | |First check Boeing Maintenance Manual 31-31-01 and make sure you are| | |loading the correct mandatory and non-mandatory softwares. | | |Secondly, attempt reloading the databases before removing and | | |replacing the unit. | ................................................................................ |Note 5: |If a debug monitor is not connected or "PROC ON" was typed and the | | |fault is still present, remove and replace the unit. | ................................................................................ |Note 6: |The ground pins required to load the FDAU master controller | | |databases are not correct. This is not a hardware problem with the | | |DFDAU unit. | ................................................................................ |Note 7: |This fault is detected by the DFDAU unit when any airplane discrete | | |or database select discrete changes after the unit is running. | | |Make sure the airplane wiring for broken wires or a faulty | | |connector. | ................................................................................ |Note 8: |This fault originates at the Digital Flight Data Recorder (DFDR) and| | |not the DFDAU unit. Check the DFDR or the wiring between the DFDAU | | |and the DFDR before removing and replacing the unit. | ................................................................................ |Note 9: |The DFDAU unit has detected an error in data from an ARINC 429 port.| | |The LRU sending the data to the DFDAU unit should be checked. When | | |the airplane LRU's are powering up, and the DFDAU unit is powered up| | |first, the DFDAU unit will show the other LRU databases as inactive.| | |This fault is not an error and should go away when the inputs become| | |active to the DFDAU unit. | 2.........…....................................................................1 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：757 AMM 飞机维护手册 仪表 CHAPTER 31 - INSTRUMENTS 1(130)
