04/09/21
Message Overview:
Message Description:
Proximity Sensor Electronic Unit (PSEU) detects an internal SHORT in the Proximity Sensor PX16 Passenger Door Locked1 or in the wiring to the Proximity Sensor is shorted to the aircraft.
Possible Causes:
- Proximity Sensor Electronic Unit (PSEU) (A9)
- Passenger Door Locked 1 Proximity Sensor (PX16)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Quick Links:
| 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 |
| Built-In Test of the Door Proximity-Sensors | AMM 52-71-00-740-801 |
| Removal of the Passenger-Door Closed Proximity-Sensor | AMM 52-71-01-000-801 |
| Installation of the Passenger-Door Closed Proximity-Sensor | AMM 52-71-01-400-801 |
| Wiring - Maintenance Practices - ALL | SPM 20-12-00-02 |
| Wire Repair - Maintenance Practices - ALL | 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.
- Remove the PSEU from its rack and disconnect the splice SP126.
- Do wiring checks (shorted to ground = failure) between SP126 (pins A2, B2) and ground. Repair as required.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Replace PX16.
NOTE: Sensor resistance should be made with a meter using a < 10 mA supply of current. Never apply voltage through a sensor! Current will magnetize the sensor rendering it unreliable. Sensor resistance is typically 11 to 13 Ω.- If system checks are good, do close out.
- If fault remains, continue with next step.
- Replace PSEU.
- Do close out.
