01/20/25
Message Overview:
Message Description:
The Left DC Power-Center Protection or Right DC Power-Center Protection have reported a failure with the Left DC Power-Center Protection.
Possible Causes:
- Left DC Power-Center Protection (LPROT) (PCB1)
- Left DC Power-Center Primary-Logic (LLOG) (PCB3)
- Left DC Power-Center Power Module (PMOD) (PCB7)
- Left Power Center (LDCPC) (A35)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Full Throttle Blog/Forum Articles/Infoservice/Newsletter: None
Flight Operation Notifications Manual (FONM): None
Quick Links:
| Standard Aircraft Configuration for Maintenance | AMM 12-00-00-867-803 |
| Electrical/Electronic Safety Precautions | AMM 24-00-00-910-801 |
| Electrostatic-Discharge Safety Precautions | AMM 24-00-00-910-802 |
| Connect Electrical Power to the Aircraft | AMM 24-00-00-861-801 |
| Remove the Electrical Power from the Aircraft | AMM 24-00-00-861-802 |
| Removal of the DC Power Center (DCPC) | AMM 24-61-01-000-801 |
| Installation of the DC Power Center (DCPC) | AMM 24-61-01-400-801 |
| Removal of the DC Power-Center Primary-Logic | AMM 24-61-73-000-801 |
| Installation of the DC Power-Center Primary-Logic | AMM 24-61-73-400-801 |
| Removal of the DC Power-Center Protection | AMM 24-61-77-000-801 |
| Installation of the DC Power-Center Protection | AMM 24-61-77-400-801 |
| Wiring - Maintenance Practices - ALL | SPM 20-12-00-02 |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 |
| Electrical Connectors - Maintenance Practice - ALL | SPM 20-20-00-02 |
Troubleshooting Recommendations:
- Check in the MDC if the following fault is logged in the current faults page or in the fault history page.
- If fault is present, continue with the associated troubleshooting procedure.
- If fault is not present, continue with next step.
- Interchange the Left DC Power-Center Protection (PCB1) with the Right DC Power-Center Protection (PCB2). Is the fault message still present?
NOTE: When removing cards, take the opportunity to inspect the card connector and pins carefully.
- If YES, continue with next step.
- If NO, replace the defective DC Power-Center Protection.
- Interchange the Left DC Power-Center Primary-Logic (PCB3) with the Right DC Power-Center Primary-Logic (PCB4). Is the fault message still present?
- If YES, continue with next step.
- If NO, replace the defective DC Power-Center Primary-Logic.
- If you notice the failure is prominent on engine start or when an engine is running, swap the LH DCPC Power Module (PCB7) with the RH Power Module (PCB8). Is the fault still present on the same side?
- If YES, continue with next step.
- If NO, replace defective Power Module.
- Replace Left DC Power Center (A35).
- Do close out.