background
x
loader
Troubleshooting
arrow By ATA By Message Color By Observed Faults By CAIMS By Tips

Select color for CAS message that you wish to troubleshoot

(WARNING)
RED MESSAGE (CAUTION)
AMBER MESSAGE (ADVISORY)
CYAN MESSAGE (STATUS)
WHITE MESSAGE Require immediate crew attention. These messages are accompanied by flashing master warning, triple chime attenson with or without voice message or dedicated tone. Require immediate crew awareness and future crew action may be required in the form of alternate system selection or performance limitation. These message are accompanied by flashing master caution and a single chime. Indicate safe or normal system operation which require crew awareness, over and above the dark cockpit philosophy. Indicate minor failures or reduction in systems capability, which require no crew action.

This page includes :

For AOG assistance contact:

CRC Montreal (YUL)
Quick Links

06/20/19

Message Overview:

Fault Message:

APUGCU [OVERLOAD FET/DRIVE/SENSE]

Fault Code:

2420182LPS

Associated CAS:

None

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:

Auxiliary Power Unit Generator Control Unit (APU GCU) has detected that the Overload FET Monitor and the FET drive signal do not agree, consequently resulting in the Auxiliary Power Unit (APU) Generator tripped off-line or not come on-line.

Possible Causes:

  • Auxiliary Power Unit Generator Control Unit (APU GCU) (A109)
  • AC Power Center Primary Logic Card (PLC) 1
  • AC Power Center Primary Logic Card (PLC) 2
  • AC Power Center Primary Logic Card (PLC) 3
  • AC Power Center (ACPC) (A54)
  • 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 GCU 1, GCU 2, GCU 3, GCU 4 and the APU GCU into a different position (for troubleshooting only). You can monitor the GCU faults in CAIMS via the active faults page.

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 ]
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 ]
Removal of the AC Power Center (ACPC) Primary Logic AMM 24-51-09-000-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Installation of the AC Power Center (ACPC) Primary Logic AMM 24-51-09-400-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Wire Repair - Maintenance Practices - ALL SPM 20-12-10-02 [ Global Express ]  [ G5000 ]  [ Global XRS ]

Troubleshooting Recommendations:

  1. Disconnect APU GCU connector A109P2. Access ACPC Logic assembly and remove PLC 1, 2 and 3. Do a continuity check as follows:

    From To Result
    A109P2-51 Ground

    1. If there is continuity, continue with next step.
    2. If there is no continuity, go to step 3.

    1. Disconnect ACPC connector A54P4. Do a continuity check as follows:

      From To Result
      A109P2-51 Ground

      1. If there is continuity, repair defective wiring as required and continue with next step.
      2. If there is no continuity, replace ACPC and do close out.

    2. Re-install PLC 2 and PLC 3.

      1. If system checks are good, replace PLC 1 and do close out.
      2. If fault remains, continue with next step.

    3. Remove PLC 2 and reinstall PLC 1.

      1. If system checks are good, replace PLC 2 and do close out.
      2. If fault remains, continue with next step.

    4. Remove PLC 3 and reinstall PLC 2.

      1. If system checks are good, replace PLC 3 and do close out.
      2. If fault remains, continue with next step.

    5. Replace APU GCU.
    6. Do close out.

    Registered and/or unregistered trademarks of Bombardier Inc. or its subsidiaries. © 2015 Bombardier Inc. All rights reserved.