Multiple Test Ranges: QDB-5A fault detector can test sensor signal measurements, signal simulations, fuel injectors and nozzles, ignition coils, PWM signal control components, and stepper motors Multiple Functions: Ignition drive, built-in oscilloscope display, electrical parameter (current/resistance/voltage) detection. User-friendly: Coil tester supports flexible adjustment of coil current, frequency, and duty cycle. Protection Design: It has a built-in automatic overcurrent protection mechanism. Packing Include: 1pc ignition coil tester, 1pc Power cable, 3pcs Single plugs, 1pc Idle speed stepper motor plug, 1pc Stepper motor welding cable, 1pc instruction