V-checker A622 inherited auto fault detection technology of first-generation multi-function trip computer A301 , to subversion GPS portable navigation beyond PND design constraints, and a combination of car fault detection,TPMS tire pressure monitoring, GPS navigation and fixed speed warning these four technology in one, provides the driver with the car condition monitoring, fault alarm, fuel consumption monitoring, abnormal tire pressure alarm, the GPS path navigation and traffic speed limit alert and many other features.