What is FMI 18 & How to Solve It?

What is FMI 18:

FMI 18 refers to sensor circuit short to ground. The ECM detects that the sensor circuit is shorted to ground, which can disrupt the signal and cause engine performance issues.

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Why This Happens:

• Shorted or damaged wiring in the sensor circuit.
  
• Faulty sensor causing a ground short.
  
• Loose or corroded connectors.
  
• Power supply issues or component failure.

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How to Fix It:

1. Inspect the wiring for visible damage or shorts to ground.
   
2. Test the sensor and wiring to ensure there is no continuous grounding.
   
3. Replace any damaged wiring or connectors.
   
4. Replace the faulty sensor if necessary.
   
5. Clear the fault code and verify proper operation.
   
   

How to Avoid It Before It Happens:

• Perform regular wiring inspections.
  
• Keep connectors clean and free from corrosion.
  
• Use protective coatings to prevent wear on the wiring.
  
• Clue’s equipment maintenance services track wiring integrity to detect and prevent shorts before they affect engine operation.