Fendt 1.2.84 – ECU: Engine Speed Sensor Signal Failure

The Engine Control Unit (ECU) has detected a signal failure originating from the engine speed sensor. This fault indicates that the reference voltage 2 for actuator Y035 is out of the permissible range, pointing to a problem within the engine's electronic management system. This condition causes the system to restrict performance, resulting in a noticeable reduction in engine speed and power for the operator, and an error message may appear on the display.

• Farmer 400 Vario Series
• Favorit 700 Vario Series
• Favorit 900 Vario Series
• 200 Vario Series
• 300 Vario Series
• 400 Vario Series
• 500 Vario Series
• 700 Vario Series
• 800 Vario Series
• 900 Vario Series
• 1000 Vario Series

1. 1

   Retrieve and document all active and stored fault codes using the onboard diagnostic system to identify any related faults

2. 2

   Visually inspect the engine speed sensor and its wiring harness for frayed wires, loose connections, or corrosion on the connectors

3. 3

   Ensure the electrical connector at the engine speed sensor and at the corresponding ECU pin are securely fastened

4. 4

   Check the continuity of the wiring harness between the sensor and the ECU using a multimeter to identify breaks or shorts

5. 5

   Verify that the sensor is receiving the correct reference voltage from the ECU

6. 6

   Check fuel filters and ensure adequate fuel supply, as fuel delivery issues can sometimes trigger EDC-related power loss codes

1. 1

   Safety First

   Ensure the tractor is parked on a level surface, the engine is off, and the parking brake is engaged. Disconnect the battery to prevent any electrical mishaps.

2. 2

   Locate the Engine Speed Sensor

   The engine speed sensor (B010) is typically located on the engine block, positioned to read the teeth of the flywheel or a similar rotating component. Its exact location can vary between engine models.

3. 3

   Access the Sensor

   Depending on the tractor model, it may be necessary to remove other components, such as side panels or heat shields, to gain access to the sensor.

4. 4

   Disconnect and Remove

   Disconnect the electrical connector from the sensor. Then, unbolt the sensor from its mounting position on the engine.

5. 5

   Install the New Sensor

   Install the new engine speed sensor, ensuring it is seated correctly and bolted to the manufacturer's specified torque.

6. 6

   Reconnect and Reassemble

   Reconnect the electrical connector to the new sensor. Reinstall any components that were removed to gain access.

7. 7

   Clear Fault Codes

   Reconnect the battery. Start the tractor and use the diagnostic interface to clear the 1.2.84 fault code and any other related inactive codes.

8. 8

   Verify the Repair

   Operate the tractor to ensure that the fault code does not reappear and that full engine power and speed have been restored.