Check engine light on?
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Type the code from your OBD-II scan tool. You'll get a plain-English meaning, how urgent it is, the most likely causes and the steps mechanics use to find the fault.
Most looked-up codes
Browse all 318 codesP0420Catalyst System Efficiency Below Threshold (Bank 1)P0171System Too Lean (Bank 1)P0300Random/Multiple Cylinder Misfire DetectedP0455Evaporative Emission System Leak Detected (Large Leak)P0128Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)P0442Evaporative Emission System Leak Detected (Small Leak)P0401Exhaust Gas Recirculation "A" Flow Insufficient DetectedP0016Crankshaft Position - Camshaft Position Correlation (Bank 1 Sensor A)P0700Transmission Control System (MIL Request)P0507Idle Control System RPM Higher Than ExpectedP0301Cylinder 1 Misfire DetectedP0174System Too Lean (Bank 2)
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