03/03/21
Message Overview:
Message Name:
GEN1/GCU1 OIL LEVEL SNSE FAULT
Message Code:
2421229LPS
Associated CAS:
| Reporting LRU: | Generator Control Unit (GCU) 1 |
| System Description: | 24-21-00 |
| Schematic Diagram: | 24-21-00 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wiring Diagram: | 24-21-01 [ Global Express ] [ G5000 ] [ Global XRS ] |
Message Description:
Variable Frequency Generator (VFG) 1 remote Oil Level Sensor or the Generator Control Unit (GCU) 1 sensing circuit is detected faulty by continuous Built-In Test (BIT) monitoring.
Possible Causes:
- Generator Control Unit (GCU) 1 (A56)
- Variable Frequency Generator (VFG) 1 (G1)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Notice To Operators (NTO): None
Flight Operation Notifications Manual (FONM): None
A GCU patch cable (GSE REF # 24X-24-02) can be used to interchange 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:
- Disconnect GCU 1 connector A56P2 and VFG 1 connector G1P1. Perform a continuity check as follows:
From To Result A56P2-33 Ground A56P2-60 Ground A56P2-33 A56P2-60 - If there is continuity, repair defective wiring as required and do close out.
- If there is no continuity, continue with next step.
- Perform a continuity check as follows:
From To Result A56P2-33 Backshell (Shield) A56P2-60 Backshell (Shield) - If there is continuity, repair defective wiring as required and do close out.
- If there is no continuity, continue with next step.
- Perform a continuity check as follows:
From To Result A56P2-33 G1P1-K A56P2-60 G1P1-M - If there is continuity, continue with next step.
- If there is no continuity, repair defective wiring as required and do close out.
- Interchange the GCU 1 with GCU 2. Is the fault still present?
NOTE: Allow at least 8.5 minutes for the GCU to perform its self tests (2 samples)- If YES, continue with next step.
- If NO, replace GCU 1 and do close out.
- Replace VFG 1.
- Do close out.
