John Deere 333G Barometric Pressure Sensor Fault 108-10: Diagnosis and Solutions

[MikePhua]

The John Deere 333G skid steer loader is experiencing an issue related to the barometric pressure sensor, as indicated by the fault code 108-10. This sensor is an essential component for proper engine operation, as it monitors atmospheric pressure, which helps the engine control unit (ECU) adjust fuel injection and other engine parameters. When the sensor fails, it can cause poor engine performance or prevent the equipment from starting.
Possible Causes of the Fault

1. Faulty Barometric Pressure Sensor
   The most common cause of the fault code 108-10 is a malfunctioning barometric pressure sensor. Over time, sensors can wear out or become damaged due to environmental factors, contaminants, or simply age. If the sensor is faulty, it will provide incorrect readings, leading to engine performance issues.
   
2. Wiring and Connection Issues
   A broken or loose wire, a corroded connection, or a damaged connector can cause the sensor to malfunction. The wiring harnesses connected to the sensor should be thoroughly inspected for signs of wear, corrosion, or loose connections.
   
3. Electrical Issues
   Electrical issues such as voltage fluctuations, poor ground connections, or a weak battery can affect the sensor’s operation. These issues can interfere with the sensor’s ability to communicate with the ECU.
   
4. ECU Problems
   In rare cases, the issue may lie with the ECU itself. If the ECU is not interpreting the data correctly from the barometric pressure sensor, it may trigger fault codes like 108-10. An ECU failure, though uncommon, can be costly to repair and should be considered only after other potential issues have been ruled out.
   

Troubleshooting Steps

1. Inspect the Barometric Pressure Sensor
   Start by visually inspecting the sensor for any signs of damage or wear. Ensure it is securely mounted and that its wiring is intact. If the sensor appears damaged or dirty, it may need to be replaced.
   
2. Check Wiring and Connections
   Check the wiring and connectors attached to the sensor. Look for frayed wires, corrosion, or loose connections that may be interfering with the sensor’s performance. Tighten any loose connections and replace damaged wiring.
   
3. Test the Sensor with a Multimeter
   Use a multimeter to test the sensor's resistance and voltage readings. If the readings fall outside the manufacturer’s specified range, the sensor may need to be replaced.
   
4. Inspect Electrical System
   Ensure that the electrical system, including the battery, alternator, and grounding, is functioning correctly. A weak battery or poor ground connection can cause issues with sensor readings. Check the voltage and clean any corroded terminals.
   
5. Scan for ECU Faults
   If no issues are found with the sensor or wiring, scan the ECU using a diagnostic tool to check for any stored fault codes or signs of ECU failure. If the ECU shows signs of failure, it may need to be reprogrammed or replaced.
   

Solution

1. Replace the Faulty Sensor
   If the barometric pressure sensor is confirmed to be faulty, replace it with a new one from a reputable supplier. Ensure that the replacement sensor is compatible with the John Deere 333G model.
   
2. Repair Wiring or Electrical Connections
   If there are issues with the wiring or electrical connections, repair or replace the damaged components. Ensure all connections are tight and free of corrosion.
   
3. Check ECU Calibration
   If the problem lies with the ECU, reprogramming or recalibration may be required. In some cases, the ECU may need to be replaced if it is no longer functioning correctly.
   

Conclusion
The John Deere 333G’s barometric pressure sensor fault code 108-10 is usually caused by a faulty sensor, wiring issues, or electrical system problems. By following a step-by-step troubleshooting approach, including inspecting the sensor, wiring, and electrical connections, you can identify and resolve the issue. If the problem persists, further investigation into the ECU or other related components may be necessary.