03/15/21
Message Overview:
Message Description:
PSEU Discrete Output DOT14B, MLGWOFW to Fuel System Control Unit (A57) driver failed.
Possible Causes:
- Proximity-Sensor Electronic Unit (PSEU) (A9)
- Fuel Quantity Computer (A57)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Quick Links:
| Built-In Test of the Fuel-Quantity Gauging System | AMM 28-41-00-740-801 |
| Removal of the Fuel Quantity Computer | AMM 28-41-01-000-801 |
| Installation of the Fuel Quantity Computer | AMM 28-41-01-400-801 |
| Removal of the Proximity-Sensor Electronic Unit (PSEU) | AMM 32-61-09-000-801 |
| Installation of the Proximity-Sensor Electronic Unit (PSEU) | AMM 32-61-09-400-801 |
| Functional Test of the Proximity-Sensor Electronic Unit (PSEU) | AMM 32-61-09-720-801 |
| Standard Practices - Replace Wiring | SPM 20-12-00-02 |
| Standard Practices - Wire Repair | SPM 20-12-10-02 |
Troubleshooting Recommendations:
- Pull and reset the PSEU gear system breakers (CB1-C13, CB1-C14), (CB2-C13, CB2-C14).
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Do wiring check between FSCU A57P1 pin 88 and PSEU A9AP1 pin 2H. Repair as required.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Replace PSEU.
- Do close out.


