Cummins

CODE 12

UnclassifiedFuel

What This Code Means

Low fuel level; Dirty air filter; Slow cranking speed; Fuel leak; Air leak; Under Voltage; Control is unable to maintain rated voltage

Possible Causes

  • •Low fuel level in fuel tank
  • •Dirty air filter element
  • •High oil viscosity
  • •Loose fuel fitting
  • •Excessive connected appliances (especially air conditioners and battery chargers)

Suggested Actions

  1. 1Fill the fuel tank
  2. 2Prime the engine fuel system by positioning the control switch to STOP/PRIME for 30 seconds
  3. 3Replace the air filter
  4. 4Replace engine oil with oil of proper viscosity for the ambient temperature
  5. 5Tighten any fuel fitting
  6. 6Reprime the engine fuel system by positioning the control switch to STOP/PRIME for 30 seconds
  7. 7Reduce the number of connected appliances, especially air conditioners and battery chargers
  8. 8Review load management in Loading the Generator Set

Related Cummins Fault Codes

CODE 13CODE 14ALARM ID 33CODE 1536F4C3500C3250CODE 36
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