The Power Probe IV activates components with battery power and ground for quick functional testing. The large, bright color-LCD screen allows for easy visibility for eight diagnostic testing modes. The Power Probe IV includes a 23' cable for greater reach and accessibility. Users can test the resistance of circuits in ohms, quickly read AC/DC and battery source voltage for instant voltage drop testing and easily identify the health of a fuel injector and circuit with one simple back probe. The Power Probe IV also supplies computer-safe voltage for testing PCM/ECM drivers.