What is SPN 1636 FMI 3 & How to Solve It?

What is SPN 1636 FMI 3:

SPN 1636 FMI 3 indicates a problem with the Exhaust Gas Temperature (EGT) Sensor. FMI 3 refers to an issue where the sensor is sending an incorrect signal to the ECM, affecting the exhaust gas after-treatment system and potentially causing engine mismanagement.

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Why This Happens:

• Faulty exhaust gas temperature sensor.
  
• Shorted or damaged wiring in the sensor circuit.
  
• Loose or corroded connectors.
  
• Blockages in the exhaust system.
  
• ECM failure to interpret the sensor’s signal correctly.
  
  

How to Fix It:

1. Inspect the exhaust gas temperature sensor for visible damage or malfunction.
   
2. Test the sensor’s signal to ensure it falls within manufacturer specifications.
   
3. Check the wiring and connectors for damage, corrosion, or loose connections.
   
4. Replace the faulty sensor if necessary.
   
5. Inspect the exhaust system for blockages or contamination.
   
   

How to Avoid It Before It Happens:

• Regularly inspect the exhaust gas temperature sensor and wiring.
  
• Keep connectors clean and free from corrosion.
  
• Perform routine exhaust system maintenance to ensure proper function.
  
• Monitor sensor performance with diagnostic tools.
  
• Clue’s Equipment Maintenance services monitor exhaust systems and sensors to help prevent mismanagement and ensure optimal engine performance.