10/29/19
Message Overview:
Fault Message:
GEN4 OPEN POR/FEED/GEN FAULT
Fault Code:
2424108LPS
Associated CAS:
| Reporting LRU: | Generator Control Unit (GCU) 4 |
| System Description: | 24-21-00 |
| Schematic Diagram: | 24-21-00 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wiring Diagram: | 24-21-04 [ Global Express ] [ G5000 ] [ Global XRS ] |
Fault Description:
Generator Control Unit (GCU) 4 has detected a failure (open circuit) associated with the Open Point Of Regulation (POR)/FEED/Generator (GEN) circuit and consequently Generator 4 trips off-line. Inhibited during Take-Off and Landing.
Possible Causes:
- Generator Control Unit (GCU) 4 (A59)
- Variable Frequency Generator (VFG) 4 (G4)
- 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 ] |
| Removal of the AC Power Center (ACPC) | AMM 24-51-00-000-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Installation of the AC Power Center (ACPC) | AMM 24-51-00-400-801 [ Global Express ] [ G5000 ] [ Global XRS ] |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 [ Global Express ] [ G5000 ] [ Global XRS ] |
Troubleshooting Recommendations:
- Swap GCU 4 with GCU 3 (physically or using the GCU patch cable). Is the fault still present?
- If NO, replace GCU 4 and do close out.
- If YES, continue with next step.
- Disconnect connector GCU 4 (A59P1) and ACPC (A54P2). Perform a continuity check as follows:
From To Result A59P1-A Ground A59P1-B Ground A59P1-C Ground - 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 A59P1-A A54P2-A A59P1-B A54P2-B A59P1-C A54P2-C - If there is no continuity, repair defective wiring as required and do close out.
- If there is continuity, continue with next step.
- Perform a continuity check as follows:
From To Result VFG 4 stud T1 ACPC VFG 4 stud T10 VFG 4 Stud T2 ACPC VFG 4 stud T11 VFG 4 Stud T3 ACPC VFG 4 stud T12 - If there is no continuity, repair defective wiring as required and do close out.
- If there is continuity, continue with next step.
- Disconnect ACPC studs T10, T11 and T12. Perform a continuity check as follows:
From To Result VFG 4 stud T10 Ground VFG 4 Stud T11 Ground VFG 4 Stud T12 Ground - 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 on the ACPC as follows:
From To Result A54J2-A Ground A54J2-B Ground A54J2-C Ground - If there is continuity, go to step 9.
- If there is no continuity, continue with next step.
- Perform a continuity check on the ACPC as follows:
From To Result A54J2-A ACPC VFG 4 stud T10 A54J2-B ACPC VFG 4 stud T11 A54J2-C ACPC VFG 4 stud T12 - If there is continuity, go to step 8.
- If there is no continuity, continue with next step.
- Swap VFG 4 with VFG 3. Is the fault still present?
- If NO, replace VFG 4 and do close out.
- If YES, continue with next step.
- Replace ACPC.
- Do close out.
