VDIAGTOOL Automobile Circuit Fault Detector Repair Tool 1. Can meet the needs of 2 products at the same time, simply and quickly switch from the power line probe tester function mode to the circuit breaker finder mode with just one click 2. No additional tools are required to determine the continuity of cableswires and diagnose circuit breaker points, suitable for most 12-24V cars 3. 1.77-inch color screen, showing clear data 4. Lighting in dark conditions, making it safer for you to work in the dark 5. 20FT+20FT extension cord: covers the front and rear of the vehicle, convenient for checking the entire circuit system 6. Quick self-test to ensure that it works properly before you start using it - Red light on: positive circuit - Green light on: negative circuit - Overload protection: buzzer warning 7. How to use it correctly: The probe tip (black cap) of the circuit breaker finder should be perpendicular to the wire being traced and positioned above or below it 8. Can generate activation signals for electrical components such as car lights, motors, wipers, radiator fans, relays, injectors, etc. to solve electrical problems; locate car short circuits if you keep blowing fuses, also test various sensors, signal circuits to find out the root cause of electrical problems 9. 4 working modes, just switch the mode button: - DC voltage test: DC voltage detects the voltage value of the circuit under test with a resolution of 0.1 volt - AC voltage test: detects the maximum value of AC voltage. voltage, minimum voltage and frequency of the circuit under test - Resistance test: Detects the resistance between the circuit probe tip and the auxiliary ground wire to determine whether the circuit is complete or disconnected, and whether the resistance of the component meets the manufacturer's specifications - Diode test: Detects the operation of the diode component and determines whether it is conducting, showing the actual forward voltage when the diode conducts current 10.