In modern automotive diagnostic systems, the process of clearing Diagnostic Trouble Codes (DTCs) involves much more than simply deleting stored faults from the ECU. After a fault clear request is performed using the UDS service 0x14 (Clear Diagnostic Information), the control module may execute additional internal routines to ensure that the system is properly reinitialized and synchronized. These routines are commonly triggered through the UDS service 0x31 (RoutineControl), such as routine 0x0F06, which can be used to reset internal diagnostic flags, clear memory states, or reinitialize monitoring functions inside the ECU. Once the routine is completed, the diagnostic scanner typically verifies the success of the operation using services like 0x22 (ReadDataByIdentifier) to confirm that the fault memory has been correctly cleared. Understanding these communication sequences is essential for the development of ECU emulators, diagnostic tools, and CAN traffic analysis systems, since an incorrect response during these routines may cause the scanner to fail the clear procedure or detect communication errors with the vehicle module.
