tests battery voltage
checks the battery condition while starting the engine checks interior and exterior lamps checks relays,power windows and electric motors LED light source it also has a powerful light source,circuit breakre protectd voltagesource and a warning buzzer power supply functions may be selected protects wires and components when testing shorted and overloaded circuits finds open and disconnected pares there is magnet near the back side og the device,so you can attach the device on the vehicle for easy use