04/08/21
Message Overview:
Message Description:
ARINC 429 R-File Server Unit (FSU)-1 data bus is reported absent by the Right Input/Output Concentrator (R IOC) and by the right Multi-Function Display (R MFD).
Possible Causes:
- File Server Unit 2 (FSU 2) (A222)
- Right Input/Output Concentrator (R IOC) Unit (A4-IOC2)
- Right Multi-Function Display (R MFD) (A28)
- Integrated Avionics Processing System (IAPS) (A4)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Quick Links:
| Removal of the Integrated-Avionics Processor System (IAPS) Card Cage (ICC) | AMM 31-45-01-000-801 |
| Installation of the Integrated-Avionics Processor System (IAPS) Card Cage (ICC) | AMM 31-45-01-400-801 |
| Removal of the Input/Output Concentrator Unit (IOC) | AMM 31-45-05-000-801 |
| Installation of the Input/Output Concentrator Unit (IOC) | AMM 31-45-05-400-801 |
| Removal of the Adaptive Flight-Display Unit | AMM 31-61-01-000-801 |
| Installation of the Adaptive Flight-Display Unit | AMM 31-61-01-400-801 |
| Removal of the File Server Unit (FSU) | AMM 46-21-01-000-801 |
| Installation of the File Server Unit (FSU) | AMM 46-21-01-400-801 |
| Wiring - Maintenance Practices - ALL | SPM 20-12-00-02 |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 |
Troubleshooting Recommendations:
- Reset R FILE SERVER (CB2-C6) circuit breaker.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Ensure power and grounds are available at FSU 2.
28 VDC PWR GND Chassis GND A222P1-14 A222P1-47 A222P1-35 A222P1-67 A222P1-68 - If 28 VDC and grounds are available at FSU 2, go to step 4.
- If 28 VDC and/or grounds are not available at FSU 2, continue with next step.
- Do wiring check between FSU 2 connector A222P1 and circuit breaker CB2-D6 R FILE SERVER. Replace/repair as required.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Swap IOCs.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Swap MFDs.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Swap FSUs.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Do wiring check of the ARINC 429 R-FSU-1 data bus between FSU 2 connector A222P1 and IAPS connector A4P101. Replace/repair as required.
- If system checks are good, do close out.
- If fault remains, continue with next step.
NOTE: An internal short of any LRU connected to this ARINC data bus may cause the fault.
- Do wiring check of the Ethernet buses (transmit/receive) between FSU 2 connector A222P1 and R MFD connector A28P1. Replace/repair as required.
- If system checks are good, do close out.
- If fault remains, continue with next step.
NOTE: An internal short of any LRU connected to these data buses may cause the fault.
- Replace IAPS Card Cage (ICC).
- Do close out.