04/07/21
Message Overview:
Message Description:
No Maintenance Diagnostic Computer (MDC-2) data received at Right Multi-Function Display (R-MFD) and in Maintenance Mode.
Possible Causes:
- Maintenance Diagnostic Computer (MDC) (A4-MDC)
- Right Multi-Function Display 2 (R-MFD) (A28)
- Integrated-Avionics Processor System (IAPS) Card Cage (ICC) (A4)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Quick Links:
| Removal of the Junction Box JB4 | AMM 24-63-13-000-802 |
| Installation of the Junction Box JB4 | AMM 24-63-13-400-802 |
| Functional Test of Junction Box JB4 | AMM 24-63-13-720-801 |
| Operational Test of the Integrated-Avionics Processor System (IAPS) | AMM 31-45-00-710-801 |
| 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 |
| Operational Test of the Input/Output Concentrator Unit (IOC) | AMM 31-45-05-710-801 |
| Removal of the Data Base Unit | AMM 34-61-09-000-801 |
| Installation of the Data Base Unit | AMM 34-61-09-400-801 |
| Operational Test of the Data Base Unit | AMM 34-61-09-710-801 |
| Operational Test of the Maintenance Diagnostic System | AMM 45-45-00-710-801 |
| Removal of the Maintenance Diagnostic Computer (MDC) | AMM 45-45-01-000-801 |
| Installation of the Maintenance Diagnostic Computer (MDC) | AMM 45-45-01-400-801 |
| Wiring - Maintenance Practices - ALL | SPM 20-12-00-02 |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 |
| Electrical Connectors - Maintenance Practice - ALL | SPM 20-20-00-02 |
Troubleshooting Recommendations:
- Reset R IAPS Circuit Breaker CB2-B6, L FILE SERVER Circuit Breaker CB1-C6 and DATA LOADER Circuit Breaker CB3-D1. Is the fault message still present?
- If NO, do close out.
- If YES, continue with next step.
- Do wiring check between IAPS Card Cage (A4), through JB4, to both PMAT Connectors (PL43 and PL42), and to DBU (A191) for the following wires:
From To Result Note Conn. A4P103 - 44 Conn. A191P1 - f Conn. A4P103 - 45 Conn. A191P1 - w Conn. A4P103 - 44 Conn. PL42J2 - 23 Conn. A4P103 - 45 Conn. PL42J2 - 24 Conn. A4P103 - 44 Conn. PL43J1 - 23 Note 1 Conn. A4P103 - 45 Conn. PL43J1 - 24 Note 1 Conn. A4P103 - 45 Conn. A221P1 - 65 Note 2 Conn. A4P103 - 45 Conn. A221P1 - 66 Note 2 - If check is satisfactory, continue with next step.
- If check is not satisfactory, repair defective wiring/connectors or JB4.
- Replace FSU 1 (A221). Is the fault still present?
- If NO, do close out.
- If YES, continue with next step.
<>NOTE: To confirm defective FSU1, FSUs can be swapped if Dual IFIS Option is incorporated.
- Replace DBU (A191), Is the fault still present?
- If NO, do close out.
- If YES, continue with next step.
- Replace MDC. Is the fault message still present?
- If NO, do close out.
- If YES, continue with next step.
- Replace IAPS Card Cage (A4).
- Do close out.