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

06/29/21

Message Overview:

Message Name:

ACPC CCBP/AC ESS BUS FAILED

Message Code:

2451389ACP

Associated CAS:

ELEC SYS FAIL
(Caution)

Reporting LRU: AC Power Center (ACPC)
System Description: 24-50-00
Schematic Diagram: 24-23-00 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Wiring Diagram: 24-52-01 [ Global Express ]  [ G5000 ]  [ Global XRS ]

Message Description:

AC Power Center (ACPC) detects that the AC ESS BUS is unpowered while it is connected to an active power source.

Possible Causes:

  • AC Power Center (ACPC) Contactor (K25)
  • Secondary Logic Card (SLC) 4
  • Ram Air Turbine Line Contactor (RATLC) (K3)
  • AC Power Center (ACPC) (A54)
  • Associated Wiring

Troubleshooting Tips:

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

Flight Operation Notifications Manual (FONM): None

Quick Links:

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) Secondary Logic AMM 24-51-13-000-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Installation of the AC Power Center (ACPC) Secondary Logic AMM 24-51-13-400-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Removal of the AC Power Center (ACPC) H-Series Contactor AMM 24-51-29-000-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Installation of the AC Power Center (ACPC) H-Series Contactor AMM 24-51-29-400-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Removal of the AC Power Center (ACPC) Electronic Modules AMM 24-51-81-000-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Installation of the AC Power Center (ACPC) Electronic Modules AMM 24-51-81-400-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Removal of the Cockpit Circuit-Breaker Panel (CCBP) H-Series Contactors AMM 24-52-05-000-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Installation of the Cockpit Circuit-Breaker Panel (CCBP) H-Series Contactors AMM 24-52-05-400-801 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Access to System Diagnostics AMM 45-45-00-970-804 [ Global Express ]  [ G5000 ]  [ Global XRS ]
Wire Repair - Maintenance Practices - ALL SPM 20-12-10-02 [ Global Express ]  [ G5000 ]  [ Global XRS ]
AC Power Center Component Maintenance Manual CMM 24-51-02 [ Global Express ]  [ G5000 ]  [ Global XRS ]

Troubleshooting Recommendations:

  1. Apply power to the Aircraft. Is AC BUS 4 powered?

    1. If NO, use the AC BUS 4 FAIL troubleshooting page to find the cause and continue with next step.
    2. If YES, continue with next step.

  2. Access CAIMS from the PMAT. Select SYSTEM DIAG, ATA 24, AC POWER CENTER ACPC A, LRU TEST. Make a selection of AC SYNOPTIC DATA and go to page 4/5. Does "AC ESS FEEDER" show as powered?

    1. If YES, go to step 10.
    2. If NO, continue with next step.

  3. Access CAIMS from the PMAT. Select SYSTEM DIAG, ATA 24, AC POWER CENTER ACPC A, LRU TEST. Make a selection of AC SYNOPTIC DATA and go to page 5/5. Does "AC ESS BUS" show as Connected?

    1. If NO, go to step 5.
    2. If YES, continue with next step.

  4. Access the ACPC Logic sub-assembly. Interchange SLC 4 with SLC 3. Did the CAIMS message clear?

    1. If YES, replace SLC 4 and do close out.
    2. If NO, put the cards back in their original location and continue with next step.

  5. Access the ACPC Logic sub-assembly. Remove SLC 4 and access the ACPC Secondary Power sub-assembly. Disconnect EM 2 connector P206 and K25-12, K25-11 and perform a continuity check as follows:

    From To Result
    K25-X1 Ground
    K25-X2 Ground
    K25-Y1 Ground
    K25-Y2 Ground
    K25-12 Ground

    1. If there is continuity, go to step 9.
    2. If there is no continuity, continue with next step.

  6. Perform a continuity check as follows:

    From To Result
    K25-11 Ground

    1. If there is no continuity, go to step 9.
    2. If there is continuity, continue with next step.

  7. Perform a continuity check as follows:

    From To Result
    K25-X1 P206-5
    K25-X2 P411A-11
    K25-Y1 K25-X1
    K25-Y2 P411A-10
    K25-112 P411C-12

    1. If there is no continuity, go to step 9.
    2. If there is continuity, continue with next step.

  8. Interchange contactor K25 with K21 and perform a system checks. Did the CAIMS fault message clear?

    1. If YES, replace contactor K25 and do close out.
    2. If NO, continue with next step.

  9. Replace ACPC.

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

  10. Access the RATLC (K3) in the copilot side circuit breaker panel and perform a 115 VAC Voltage check as follows:

    From To Result
    K3-A3 Ground
    K3-B3 Ground
    K3-C3 Ground

    1. If one or more phase is missing 115 VAC, repair defective wiring as required and do close out.
    2. If there is 115 VAC, continue with next step.

  11. Replace RATLC (K3).
  12. Do close out.
    ac_ess_bus_fail

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