Fault code library
7,726 OBD codes. Every warning light explained in plain English.
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Click a code type to see an explanation, the most common codes, and the full list.
Most searched codes
The fault codes drivers look up most often.
P0300
Random/Multiple Cylinder Misfire Detected
P0420
Catalyst System Efficiency Below Threshold (Bank 1)
P0171
System Too Lean (Bank 1)
P0401
EGR Flow Insufficient Detected
P0442
Evaporative Emission Control System Leak Detected (small leak)
P0455
Evaporative Emission Control System Leak Detected (Gross Leak)
P0430
Catalyst System Efficiency Below Threshold (Bank 2)
P0101
Mass Air Flow (MAF) Circuit Range/Performance
P0113
Intake Air Temperature Sensor 1 Circuit High Input
P0700
Transmission Control System Malfunction
P0234
Turbocharger/Supercharger "A" Overboost Condition
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