If the screen remains blank, check the vehicle’s cigarette lighter fuse (oddly, some OBD2 ports share this circuit). If the tool says "Linking Error," ensure your vehicle is OBD2 compliant (USA 1996+, Europe 2001+ gasoline).
A crucial part of the is understanding the interface. The device is designed to be held comfortably in one hand, featuring a small LCD screen and a membrane keypad. memoscan u480 user manual