02/25/21
Message Overview:
Message Description:
Fault in FIREX Control Unit (CU) Bottle 2 discretes output to Data Concentrator Unit (DCU) is detected.
Possible Causes:
- Fire-Detection-and-Extinguishing Control Unit (FIREX CU) (A91)
- Data Concentrator Unit (DCU) (A14)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Quick Links:
| Removal of the Fire-Detection-and-Extinguishing (FIREX) Control-Unit | AMM 26-11-01-000-801 |
| Installation of the Fire-Detection-and-Extinguishing (FIREX) Control-Unit | AMM 26-11-01-400-801 |
| Removal of the Data Concentrator Unit (DCU) | AMM 31-41-01-000-802 |
| Installation of the Data Concentrator Unit (DCU) | AMM 31-41-01-400-802 |
| Wiring - Maintenance Practices - ALL | SPM 20-12-00-02 |
| Wire Repair - Maintenance Practices - ALL | SPM 20-12-10-02 |
Troubleshooting Recommendations:
- Perform wiring check (short circuit to ground) between FIREX control unit (A91P1 pin 20, A91P1 pin 39, A91P2 pin 20, and A91P2 pin 6) and DCU (A14EP1 pin 11J, A14BP1 pin 11E, A14EP1 pin 12J, and A14EP1 10J) (repair as required).
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Replace FIREX control unit.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Replace DCU.
- Do close out.