Car diagnostic codes – what they mean and how to deal with them

Decoding OBD-II diagnostic trouble codes

Understanding fault codes is an important part of vehicle maintenance. Our full list will help you interpret the codes so you can troubleshoot your car yourself.

Search your trouble code
List of the most common DTC codes – find the meaning and learn how to solve the problem

Top 50 fault codes

View the full list of codes
P0420
P0171
P0300
P0113
P0340
P0335
P0128
P0011
P0016
P0102
P0135
P0172
P0299
P0301
P0401
P0430
P0087
P0101
P0141
P0174
P0302
P0303
P0304
P0441
P0442
P0700
P0014
P0031
P0106
P0118
P0446
P0500
P0010
P0122
P0134
P0138
P0325
P0341
P0443
P0017
P0030
P0037
P0089
P0100
P0107
P0108
P0121
P0130
P0234
P0403
During vehicle diagnostics, an OBD2 scanner displays all malfunctions as fault codes. On this page, you can find out what they mean and what the difference between them is. Our comprehensive list will help you interpret OBD2 codes, so you can easily find out more about the malfunction online free of charge and repair your car yourself.
The ECU fault code can tell you exactly what problem your vehicle has

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The ECU fault code can tell you exactly what problem your vehicle has

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