One of the most fundamental aspects on the behaviour of a general electronic control modules (ECUs), is the management of the diagnostic trouble code (DTCs). The DTC is a standardised numerical code used in order to identify and store malfunctions or faults detected by the ECU. Each code represents a specific type of fault, facilitating identification, diagnosis and troubleshooting in automotive embedded systems. For this reason, it is crucial to verify whether the ECU manages these identifications codes as expected. In particular, to validate the DTCs of a specific ECU, it is necessary to check when the ECU sets a given DTC after fault injection, and when it deactivates it once the fault is removed.