Basic OBD readers are fine for reading a quick check engine light, but they...

https://wiki-triod.win/index.php/The_Shop_Floor_Reality:_Why_Diagnostics_Beat_Guesswork_in_Engine_Management

Basic OBD readers are fine for reading a quick check engine light, but they don't show you the full story. Modern cars are rolling computers with dozens of interconnected ECUs that control everything from your transmission to your door locks