About AutoDiag

AutoDiag helps drivers, DIYers and mechanics make sense of the trouble codes a scan tool reads from a car's computer. For each code we explain what it means in plain English, how urgent it is, what usually causes it and the order a good mechanic would check things in, so you can avoid replacing parts you don't need.

Where the information comes from

Code titles follow the SAE J2012 standard used by all OBD-II vehicles. Causes and diagnostic steps are general guidance drawn from common repair practice. Videos come from YouTube channels run by working mechanics and technicians; the videos belong to their creators and are embedded from YouTube.

Disclaimer

Every vehicle is different. Always confirm specifications and procedures with the service manual for your vehicle or a qualified mechanic. Work on vehicles carries real risks: support a raised car on axle stands, never under a jack alone; let engines and cooling systems cool before opening them; disconnect the battery before electrical work; and leave airbag, high-pressure fuel and hybrid high-voltage systems to trained professionals. AutoDiag is not responsible for any damage or injury resulting from the use of this information.