06/25/19
Message Overview:
Fault Message:
GCU2 [OPEN CIRCUIT TR4]
Fault Code:
2422106LPS
Associated CAS:
| Reporting LRU: | Generator Control Unit (GCU) 2 |
| System Description: | 24-21-00 |
| Schematic Diagram: | 24-21-00 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wiring Diagram: | 24-21-02 [ Global Express ] [ G5000 ] [ Global XRS ] |
Fault Description:
Generator Control Unit (GCU) 2 has detected a failure (open circuit) associated with Transistor (TR4), consequently resulting in Generator 2 to tripped off-line or not come on-line.
Possible Causes:
- Generator Control Unit (GCU) 2 (A57)
- Variable Frequency Generator (VFG) 2 (G2)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
A GCU patch cable (GSE REF # 24X-24-02) can be used to swap GCUs 1, 4 and 5 into position 2 or 3 (for troubleshooting only).
The GCU NVMs can only be downloaded at position #2 or #3.
Quick Links:
| Removal of the Variable Frequency Generators (VFG) | AMM 24-21-01-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Variable Frequency Generators (VFG) | AMM 24-21-01-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Removal of the Generator Control Units (GCU) | AMM 24-24-01-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the Generator Control Units (GCU) | AMM 24-24-01-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 [ Global Express ] [ G5000 ] [ Global XRS ] |
Troubleshooting Recommendations:
- Do a complete aircraft power reset. Is the fault still present?
- If NO, monitor for failure and do close out.
- If YES, continue with next step.
- Swap GCU 2 with GCU 1 (Physically or using the GCU patch cable).
- If system checks are good, replace GCU 2 and do close out.
- If fault remains, continue with next step.
- Replace VFG 2.
- Do close out.