What is SPN 157 CUMMINS & How to Solve It?

What is SPN 157 CUMMINS:

SPN 157 in Cummins engines refers to a fault in the Coolant Temperature Sensor Circuit. The ECM has detected that the coolant temperature sensor is not operating within the expected voltage range, potentially leading to incorrect readings of coolant temperature, which could result in engine overheating or poor performance.

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Why This Happens:

• Faulty coolant temperature sensor.
  
• Damaged or shorted wiring in the sensor circuit.
  
• Loose or corroded sensor connectors.
  
• Low coolant levels affecting the sensor’s performance.
  
• ECM misinterpretation of the sensor signal.
  
  

How to Fix It:

1. Inspect the coolant temperature sensor for visible damage or malfunction.
   
2. Test the sensor’s voltage and resistance to verify proper operation.
   
3. Check wiring and connectors for damage or corrosion.
   
4. Replace the faulty sensor if necessary.
   
5. Ensure proper coolant levels and perform a system check.
   
   

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 replace coolant at recommended intervals.
  
• Perform diagnostic checks to ensure accurate sensor readings.
  
• Clue’s Equipment Maintenance services help monitor coolant system health and prevent sensor-related issues before they affect engine performance.