03/16/26
Message Overview:
Message Name:
OIL PRESSURE SENSOR 1A
Message Code:
B3-303642
Associated CAS:
| Reporting LRU: | L ENG OIL PRES |
| System Description: | 79-30-00 - Indicating |
| Schematic Diagram: | SSM 79-31-00-101 - Oil Indication System |
| Wiring Diagram: | None |
Message Description:
Left engine oil pressure sensor fault 1A.
[MCID 1001]
Oil Pressure Sensor 1A.
Detection of a fault in the oil pressure sensor harness or between the oil pressure sensor and the ECU A. The ECU A cannot support full system operation.
Possible Causes:
- Oil Pressure Transducer
- Wiring Harness (W6)
- Wiring Harness (W4)
- Full Authority Digital Engine Control Unit (FADEC) Electronic Control Unit A (ECU) (A41)
Troubleshooting Tips:
Advisory Wire/Service Bulletin: None
Full Throttle Blog/Forum Articles/Infoservice/Newsletter: None
Flight Operation Notifications Manual (FONM): None
Quick Links:
| General Setup for Maintenance | |
|---|---|
| Standard Aircraft Configuration for Maintenance | AMM 12-00-00-867-803 |
| Connect Electrical Power to the Aircraft | AMM 24-00-00-861-801 |
| Remove Electrical Power from the Aircraft | AMM 24-00-00-861-802 |
| Electrical/Electronic Safety Precautions | AMM 24-00-00-910-801 |
| Electrostatic Discharge Safety Precautions | AMM 24-00-00-910-802 |
| Maintenance Tasks | |
| Removal of the Engine Electronic Control Unit (ECU) | AMM 76-10-05-000-801 |
| Installation of the Engine Electronic Control Unit (ECU) | AMM 76-10-05-400-801 |
| Removal of the Oil Pump | AMM 79-21-01-000-802 |
| Installation of the Oil Pump | AMM 79-21-01-400-802 |
| Removal of the Oil Filter | AMM 79-21-05-000-801 |
| Installation of the Oil Filter | AMM 79-21-05-400-801 |
| Removal of the Chip Detector | AMM 79-21-09-000-801 |
| Installation of the Chip Detector | AMM 79-21-09-400-801 |
| Removal of the Oil Filter Bypass-Indicator | AMM 79-31-01-000-802 |
| Installation of the Oil Filter Bypass-Indicator | AMM 79-31-01-400-802 |
| Removal of the Oil Temperature Transducer | AMM 79-31-05-000-801 |
| Installation of the Oil Temperature Transducer | AMM 79-31-05-400-801 |
| Removal of the Oil Pressure Transducer | AMM 79-31-09-000-801 |
| Installation of the Oil Pressure Transducer | AMM 79-31-09-400-801 |
| Removal of the Oil Level Probe | AMM 79-31-13-000-801 |
| Installation of the Oil Level Probe | AMM 79-31-13-400-801 |
Troubleshooting Recommendations:
- Isolate per the Light Engine Maintenance Manual Subtask 72-00-00-810-161-A01, System Check 4, and MCID 1001.
- Disconnect and examine the OIL PRESS connector W4P12 for damaged wires and other damage. (Refer to LEMM TASK 76-10-01-050-801, Removal).
- Apply 10 VDC to the system.
- Do a check to measure supply voltage at the pressure sensor as shown in the list below.
Connector Pins Reading Input Check W4P12 1, 2 10 VDC W4P12 7, 8 10 VDC Output Check W4P12 3, 4 0.325 to 0.675 VDC W4P12 9, 10 0.325 to 0.675 VDC - With power removed, do a internal short check at the connector as shown in the list below
Connector: To: From: W4P12 1 2 W4P12 7 8 - Disconnect and examine the INTERFACE connector W4P1 for damaged wires and other damage. (Refer to LEMM TASK 76-10-01-050-801, Removal).