Fendt 1.2.0E – A051 - ECU, Engine Control Unit (EDC 7): B090 - Sensor, oil pressure

Cable break in the wiring, a short circuit, or that the engine oil pressure is outside of the set-point range (too low or an implausible value).

• 411 Vario COM III
• 412 Vario COM III
• 413 Vario COM III
• 414 Vario COM III
• 415 Vario COM III
• 712 Vario COM III
• 714 Vario COM III
• 716 Vario COM III
• 718 Vario COM III
• 818 Vario COM III
• 820 Vario COM III
• 309 Vario COM III
• 310 Vario COM III
• 311 Vario COM III
• 312 Vario COM III
• 409 Vario COM III
• 410 Vario COM III
• 711 Vario COM III
• 815 Vario COM III
• 817 Vario COM III
• 916 Vario COM III
• 920 Vario COM III
• 924 Vario COM III
• 926 Vario COM III
• 930 Vario COM III
• 936 Vario COM III

1. 1

   Verify actual engine oil pressure using a mechanical gauge or diagnostic software. If the mechanical pressure is actually low (below 0.9 bar at 800 rpm, 1.5 bar at 1300 rpm, or 2.0 bar at 1900 rpm), this indicates an internal engine lubrication issue rather than a sensor fault.

2. 2

   Inspect the wiring harness at separation point X1659 (the connector for the B090 sensor) for breaks, corrosion, or short circuits.

3. 3

   Test the sensor supply and signal voltages on the 4-pin connector (Pin 1: +5.0 VDC supply, Pin 2: Signal, Pin 4: Ground).

1. 1

   Locate the Sensor

   The B090 oil pressure sensor is located on the right side of the engine, typically on the bottom left of the oil filter housing. You may need to open the bonnet and remove a metal side panel to access it.

2. 2

   Disconnect the Battery

   Always disconnect the battery before servicing engine management sensors.

3. 3

   Remove the Sensor

   Disconnect the wiring harness at separation point X1659. Unscrew the faulty B090 sensor from the oil filter housing. Have a rag ready, as a small amount of oil may weep from the port.

4. 4

   Install the New Sensor

   Thread the new sensor into the housing. (Do not over-tighten; use moderate torque and an oil-compatible thread sealant if the new sensor does not come pre-coated).

5. 5

   Reconnect and Reassemble

   Reconnect the X1659 wiring harness plug and reinstall any metal panels that were removed.

6. 6

   Clear Fault Codes

   Connect the SERDIA or FENDIAS diagnostic tool and delete the stored error codes (associated sub-codes for this fault are FC: 00C4, 00C5, 00C6, 00C7).

7. 7

   Test

   Start the tractor and verify that the oil pressure warning is gone and that the ECU is registering the correct pressure at idle and high RPM.