Each module communicates with other modules or sensors (here an overview of the modules). If an error such as the module to be asked receives no answer, an incorrect answer or the answer is too late, this is stored as an error (DTC) in the module.
Depending on the error, these remain permanently stored (until you delete them via the OBD2 interface) or the errors are deleted by the module itself after a certain time. Many of these errors are not critical and will be read out and processed and deleted for diagnostic purposes during the next service. Other errors, on the other hand, are critical and the driver is also informed about them, namely about the instrument cluster via a corresponding lamp.
The errors can be read out and deleted via FORScan. Some errors are described in detail in the program, but not for others. Therefore, here is a compilation of the error codes.
Structure of an error code
The error code consists of a letter and subsequent numbers. Here is a picture that explains this clearly:
The example above makes it easier to map error codes to which there is no description.
An overview of the B-codes
An overview of the C-codes
An overview of the P-codes
An overview of the U-codes