What is FMI 31:
FMI 31 refers to Out-of-Range or Unreliable Sensor Signal. The ECM detects that the sensor is providing a signal that is either too high, too low, or inconsistent, leading to potential engine performance issues.
Why This Happens:
- Faulty sensor or malfunctioning wiring.
- Shorted or open circuits in the sensor circuit.
- Loose or corroded connectors.
- Environmental factors affecting sensor readings.
- ECM failure to interpret the sensor’s data.
How to Fix It:
- Inspect the sensor and wiring for visible damage or malfunction.m
- Test the sensor’s output against manufacturer specifications.
- Check connectors for tightness and cleanliness.
- Replace the faulty sensor if necessary.
- Ensure stable voltage supply and proper ECM communication.
How to Avoid It Before It Happens:
- Regularly inspect sensors and wiring for damage.
- Perform routine diagnostic checks to monitor sensor performance.
- Keep connectors clean and corrosion-free.
- Clue’s equipment maintenance services track sensor performance and help prevent errors before they disrupt engine operation.
