What is SPN 110 FMI 15 & How to Solve It?

What is SPN 110 FMI 15:

SPN 110 refers to Engine Coolant Temperature, and FMI 15 means the sensor is reporting a value above the expected range.

This code signals a potential overheating condition or a failing temperature sensor providing a falsely high reading.

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Why This Happens

• Actual coolant temperature is too high.
  
• Faulty coolant temperature sensor.
  
• Wiring shorted to voltage.
  
• ECM misinterpreting signal due to electrical noise.
  

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How to Fix It

1. Check coolant level and radiator for clogs or leaks.
   
2. Test the coolant temperature sensor with diagnostics.
   
3. Inspect wiring and connector for heat damage.
   
4. Replace the sensor if values are stuck or too high.
   
5. Clear the code and confirm engine cools properly.
   

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How to Avoid It Before It Happens

1. Replace temperature sensors during coolant flush intervals.
   
2. Protect coolant wiring from high heat exposure.
   
3. Keep radiator and cooling system clean and serviced.
   
4. Monitor warm-up rates and high-load temperatures.