Operation Instruction:1.Turn off the vehicle's engine.2.Connect the black clip to the negative terminal of the vehicle battery, connect the red clip to the terminal of the battery.3.Locate the fuel injector which you to test, then remove the electrical cable from this injector and connect the tester's two output terminals to the electrical connector of this injector.4.Press the MODE SET key to select the mode, the display shows the current mode.Injector Tester Specification:Power Supply:12V vehicle batteryOperation Environment:0-40C,relative humidity Less than 80%Storage Environment:-10C ~50C, relative humidity Less than 85%Test Cable Length: 41.5cm/ 16.3 inchesProduct Size:147x82x29mmExplanations for the 4 Modes:Mode1: the tester will output 1 , whose width is about 250ms.Mode 2: the tester will output 50 pulses, 's width is about 7ms.Mode 3: the tester will output 100 pulses, 's width is about 3.5ms.Mode 4: the tester will output continuously at the rate of 50 pulses per about 1450ms, 's width is about 7ms.At any time, you can press the key again to stop outputting pluse.5. After you have the mode, press the key.The tester outputs (s) to the injector under test, the signal indicator will light as indication.Material:ABScolour:blackPackage Contents:1 * Injector TesterOnly the above package content, other are not included.Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.