John Deere ECU002795.03 – ECU: Turbocharger Position Sensor Circuit Fault

The Engine Control Unit (ECU) has detected a problem within the electrical circuit of the turbocharger's position sensor. This sensor provides critical feedback to the ECU about the precise physical position of the Variable Geometry Turbocharger (VGT) internal vanes, which is used to manage boost pressure according to engine load and speed. A fault in this circuit disrupts the control loop, causing the engine power to be limited and the Active Exhaust Filter cleaning function to become unavailable. Continued operation may result in a loss of machine availability.

• 4.5L Engine
• 6.8L Engine
• 4045HFC92
• Sullair 375 air compressors
• 6090HFC94
• 6090HFG94
• R Series Tractors
• R4038 Sprayer
• 9770 STS Combine

1. 1

   Visually inspect the turbocharger position sensor, its wiring harness, and connectors for any signs of damage, corrosion, or loose connections

2. 2

   With the engine off, manually push the turbocharger actuator piston to check its movement. It should require approximately 45 lbs of force and move about 10mm smoothly. If sticking, it indicates a turbocharger issue such as carbon buildup

3. 3

   Connect John Deere Service Advisor and monitor the 'vein position input voltage' while manually moving the actuator piston in and out. A normally functioning sensor should show a smooth change in voltage (typically ranging from 0.8V to 4.0V)

4. 4

   If sensor voltage readings are erratic, static, or out of range, perform a harness test to check for continuity, shorts to power, or shorts to ground in the wiring between the sensor and the ECU

5. 5

   Check for other active or stored fault codes related to the turbocharger or engine control system

1. 1

   Ensure Safety

   Turn off the engine and allow the turbocharger and exhaust components to cool down completely before beginning work.

2. 2

   Access the Sensor

   Locate the turbocharger position sensor on the turbocharger assembly. Its exact location can vary depending on the engine model.

3. 3

   Disconnect and Remove

   Carefully disconnect the electrical connector from the sensor. Remove the bolts or screws securing the sensor to the turbocharger and remove the old sensor.

4. 4

   Install New Sensor

   Install the new position sensor, ensuring it is seated correctly. Tighten the retaining bolts to the manufacturer's specified torque.

5. 5

   Reconnect and Verify

   Reconnect the electrical connector.

6. 6

   Calibrate and Test (If Required)

   After installation, start the engine and use Service Advisor to verify that the new sensor is providing a correct voltage signal and that the ECU002795.03 fault code does not return. Some new VGT components require calibration using Service Advisor after installation.

7. 7

   Field Test

   Operate the machine under normal conditions to ensure the power limitation is gone and all functions have been restored.