06/20/19
Message Overview:
Fault Message:
APUGCU [GCS OFF SENSE]
Fault Code:
2420209LPS
Associated CAS:
| Reporting LRU: | Auxiliary Power Unit Generator Control Unit (APU GCU) |
| System Description: | 24-22-00 |
| Schematic Diagram: | 24-22-00 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wiring Diagram: | 24-22-01 [ Global Express ] [ G5000 ] [ Global XRS ] |
Fault Description:
The Auxiliary Power Unit Generator Control Unit (APU GCU) has detected an internal failure related to the Generator Control Switch (GCS PBA) selection to the ON position sensing circuit and, consequently resulting in APU Generator tripped off-line.
Possible Causes:
- Auxiliary Power Unit Generator Control Unit (APU GCU) (A109)
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
The GCU NVMs can only be downloaded at position #2 or #3.
A GCU patch cable (GSE REF # 24X-24-02) can be used to swap GCU 1, GCU4 and APU GCU into position 2 or 3 (for troubleshooting only).
Quick Links:
| 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 ] |
Troubleshooting Recommendations:
- Replace APU GCU. NOTE: Use PMAT to monitor the fault on GCU.
- Do close out.