The diagnostic trouble code (DTC) is a code generated by a vehicle’s onboard diagnostics (OBD) system. It’s also known as an OBD code, OBD-II code (the second generation of onboard self-diagnostics), or engine fault code, and it helps narrow down the cause of a specific problem.
There are generic and manufacturer-specific codes. “Generic” means that the trouble code will indicate the same issue across different OBD-II vehicles regardless of make, while”manufacturer-specific” means the code is specific to the vehicle manufacturer.