03/11/21
Message Overview:
Message Description:
PSEU detects an OPEN circuit within the proximity sensor PX02 Left Main Landing Gear WOW1 or in the wiring to the proximity sensor or aircraft.
Possible Causes:
- Proximity-Sensor Electronic Unit (PSEU) (A9)
- Left Main Landing-Gear Weight-On-Wheels 1 Proximity-Sensor (PX02)
- Associated Wiring
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Forum Articles/Infoservice/Newsletter: None
Quick Links:
| Removal of the Main Landing-Gear (MLG) Proximity-Sensors | AMM 32-61-01-000-801 |
| Installation of the Main Landing-Gear (MLG) Proximity-Sensors | AMM 32-61-01-400-801 |
| 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 |
| 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 continuity wiring check between PSEU A9AP1 and LEFT MAIN GEAR WOW 1 (INBOARD) Proximity Sensor PX02. Repair as required.
From: To: Expected Results: PSEU A9AP1Pin 1B J511 Pin4 ≈0Ω PSEU A9AP1Pin 2B J511 Pin5 ≈0Ω - If wiring checks are good, do close out.
- If fault remains, continue with next step.
- Do continuity check of LEFT MAIN GEAR WOW 1 (INBOARD) Proximity Sensor PX02. Repair as required.
CAUTION: 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.
From: To: Expected Results: PX02 P511 pin 4 P511 pin 5 11 - 13 Ω - If PX02 checks are good, do close out.
- If fault remains, continue with next step.
- Replace PX02.
- If system checks are good, do close out.
- If fault remains, continue with next step.
- Replace PSEU.
- Do close out.
