• CVN (Calibration Verification Number). EN 4. Update This module allows you to update the diagnostic software & App to the latest version. A pop-up message will indicate newer software is available if you don't update the software in the process of registration. 5. History The tablet will record the details of every diagnostic session. The History function provides direct access to the previously tested vehicles. Users can resume from the last operation, without the necessity of starting from scratch. 21