07/01/19
Message Overview:
Fault Message:
CDU 2/SPDA 4 / WRG
Fault Code:
2462802SPD
Associated CAS:
| Reporting LRU: | Secondary-Power Distribution Assembly (SPDA) 4 Electrical Management System Control-and-Display Unit (EMS CDU) 2 |
| System Description: | 24-60-00 |
| Schematic Diagram: | 24-62-01 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wiring Diagram: | 24-62-04 [ Global Express ] [ G5000 ] [ Global XRS ] 24-70-02 [ Global Express ] [ G5000 ] [ Global XRS ] |
Fault Description:
ARINC 429 communication between the Secondary-Power Distribution Assembly (SPDA) 4 and the Electrical Management System Control-and-Display Unit (EMS CDU) 2 is faulty.The Line Replaceable Unit (LRU) transmits a test label on a periodic basis and the label is echoed back by the receiving LRU.
Possible Causes:
- Electrical Management System Control-and-Display Unit (EMS CDU) 2 (A91)
- Secondary Power Distribution Assembly (SPDA) 1 (A13)
- Secondary Power Distribution Assembly (SPDA) 2 (A14)
- Secondary Power Distribution Assembly (SPDA) 3 (A15)
- Secondary Power Distribution Assembly (SPDA) 4 (A16)
- AC Power Center (ACPC) (A54)
- DC Power Center (DCPC) (A63)
- Junction Box (JB4)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Make sure the JB4 is racked properly. Field experience revealed many cases of Junction Boxes not installed properly.
Fault confirmation:
- Flight deck effect: On the EMS CDU 2, SPDA 4 electrical loads are dashed.
- Alternative fault confirmation:
- On EMS CDU No 2, select the diagnostic mode.
- Select SYSTEM - CNTL key (page 1/3).
- Select lower left side key.
- Select lower right side key.
- On EMS CDU 2, select CIRCUIT BREAKER - SYS key and counters.
- SPDA 4 IN=0=loss of communication from SPDA 4 to EMS CDU 2.
- PCDA OUT=0=loss of communication from EMS CDU 2 to ACPC, DCPC, SPDA 1, SPDA 2, SPDA 3, SPDA 4 and EMS CDU 1.
- On EMS CDU No 2, select the diagnostic mode.
Quick Links:
| Removal of the Junction Box JB4 | AMM 24-00-05-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Junction Box JB4 | AMM 24-00-05-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Junction Box JB4 Circuit-Cards | AMM 24-00-06-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Junction Box JB4 Circuit-Cards | AMM 24-00-06-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the DC Power Center (DCPC) | AMM 24-61-00-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the DC Power Center (DCPC) | AMM 24-61-00-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Secondary-Power Distribution Assemblies | AMM 24-62-01-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Secondary-Power Distribution Assemblies | AMM 24-62-01-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Electrical Management System Control-and-Display Units (EMS CDU) |
AMM 24-70-01-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Electrical Management System Control-and-Display Units (EMS CDU) |
AMM 24-70-01-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 [ Global Express ] [ G5000 ] [ Global XRS ] |
Troubleshooting Recommendations:
- Swap EMS CDU 2 with EMS CDU 1.
- If system checks are good, replace EMS CDU 2 and do close out.
- If fault remains, continue with next step.
- Swap the SPDA 4 with SPDA 2.
- If system checks are good, replace SPDA 4 and do close out.
- If fault remains, continue with next step.
- Perform wiring checks between EMS CDU 2 and SPDA 4, SPDA 3, SPDA 1, DCPC, ACPC and SPDA 2.
- If wiring checks are not good, repair defective wiring as required and do close out.
- If wiring checks are good, continue with next step.
- Replace JB4.
- Do close out.