What is SPN 8 & How to Solve It?

What is SPN 8:

SPN 8 refers to a problem with the Engine Coolant Temperature Sensor. This fault code is generated when the ECM detects that the signal from the coolant temperature sensor is outside of the expected range, potentially leading to overheating or underheating of the engine.

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Why This Happens:

• Faulty engine coolant temperature sensor.
  
• Damaged or shorted wiring in the sensor circuit.
  
• Corroded or loose connectors in the sensor circuit.
  
• Low coolant levels causing inaccurate readings.
  
• ECM failure to process the sensor’s data correctly.
  
  

How to Fix It:

1. Inspect the coolant temperature sensor for physical damage or wear.
   
2. Test the sensor’s voltage and resistance to verify it is functioning properly.
   
3. Check the wiring and connectors for visible damage or corrosion.
   
4. Replace the faulty sensor if necessary.
   
5. Ensure that coolant levels are correct and the cooling system is operating as expected.
   
   

How to Avoid It Before It Happens:

• Regularly inspect the coolant temperature sensor and wiring.
  
• Keep connectors clean and free from corrosion.
  
• Maintain proper coolant levels and monitor temperature regularly.
  
• Perform routine diagnostic checks to ensure accurate readings.
  
• Clue’s Equipment Maintenance services monitor coolant temperature sensors and help detect issues before they lead to overheating.