OBD-II Code Lookup: What Does My Check Engine Code Mean?

Read the code with any OBD2 scanner (or ask a parts store to read it), then type it here. Codes are one letter followed by four characters, like P0420.

Most searched codes

P0128Safe to DriveCoolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)P0171Fix SoonSystem Too Lean (Bank 1)P0172Fix SoonSystem Too Rich (Bank 1)P0174Fix SoonSystem Too Lean (Bank 2)P0300Stop DrivingRandom/Multiple Cylinder Misfire DetectedP0301Stop DrivingCylinder 1 Misfire DetectedP0420Safe to DriveCatalyst System Efficiency Below Threshold (Bank 1)P0430Safe to DriveCatalyst System Efficiency Below Threshold (Bank 2)P0442Safe to DriveEvaporative Emission System Leak Detected (Small Leak)P0455Fix SoonEvaporative Emission System Leak Detected (Gross Leak)P0456Safe to DriveEvaporative Emission System Leak Detected (Very Small Leak)P0700Fix SoonTransmission Control System (MIL Request)

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How severity is rated

  • Stop Driving Misfires, overheating, oil pressure or brake problems, or any flashing check engine light. Pull over and stop driving.
  • Fix Soon The engine is running too lean or rich, a large evaporative leak, or a transmission fault. Usually drivable for a short time; get it checked soon.
  • Safe to Drive Catalyst efficiency, small evaporative leaks or a slow-warming thermostat. Usually safe short term, but still get it checked and watch for a flashing light.

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