What is SPN 105 FMI 3:
SPN 105 FMI 3 refers to an issue with the Turbocharger Boost Pressure Sensor Circuit. FMI 3 indicates that the sensor is sending an out-of-range signal, affecting the ability of the ECM to correctly interpret boost pressure, leading to potential performance issues such as poor acceleration or fuel efficiency.
Why This Happens:
- Faulty turbocharger boost pressure sensor.
- Damaged or shorted wiring in the sensor circuit.
- Loose or corroded sensor connectors.
- Malfunctioning turbocharger affecting boost pressure.
- ECM misinterpretation of the sensor’s data.
How to Fix It:
- Inspect the turbocharger boost pressure sensor for damage or malfunction.
- Test the sensor’s voltage and resistance to ensure it is within specification.
- Check wiring and connectors for visible damage, corrosion, or loose connections.
- Replace the faulty turbocharger boost pressure sensor.
- Inspect the turbocharger for any mechanical issues that may be causing incorrect boost pressure.
How to Avoid It Before It Happens:
- Regularly inspect the turbocharger boost pressure sensor and wiring.
- Perform routine turbocharger system maintenance.
- Keep connectors clean and free from corrosion.
- Monitor turbo system performance using diagnostic tools.
- Clue’s Equipment Maintenance services help track turbocharger performance to ensure efficient operation and prevent sensor-related issues.
