Features:All the features of the PP1 Auto Probe but with an integral work light to aid use in dark engine bays plus an audible circuit tester for when the LED on the probe cannot be seen A brilliant tool for the auto electrician and mechanic Carry out the following tests on systems from 6V up to 24V quickly and efficiently:Polarity test Power up components prior to fitting including:Cooling fan motorsFuel pumpsWindowSunroof motorsRelays and LampsWiper motorsTests continuity in:SwitchesDiodes and FusesRelaysWiring harnessesDetect short circuits Locate bad earths quickly