Autel AL-539 AL539 Code Reader Scanner Scan Tool Car Electrical Tester with Full OBD2 Diagnoses and Avometer Function(Upgraded Version of AL519) AVOmeter Function: The Autel code reader AL539 equipped with the easy-to-read AVOmeter function for circuit test, starting test and charging system test, helping you monitor electronic-related faults of cars,which are things you cant do with the previous model, AL519. Note: Diagnose 12V systems and voltage of car battery. Full OBD2 Functions: This scan tool has full OBD2 functions for complete car diagnoses.With this car scanner you can quickly turn the check engine light off. Enter the Read codes interface from diagnostic menu, get the DTC and clear it then the MIL will be turned off. Emission Monitoring: This code scanner is equipped with practical functions of I/M Readiness check, O2 Sensor Test and On-board Monitor Test. You can pass the emission tests smoothly after checking and will not be fined because of emission problems. Information Tracking: The live data of this code reader is to show you the real-time vehicle information and the freeze frame data are the saved parameters and data when the malfunction occurred. You can know more details about your cars performance and operating status of key systems. Other Features: Besides complete OBD2 functions, this car scanner supports DTC Lookup for DTC definitions and printing via PC, which is convenient for getting the required information to help facilitate your repair work. Color Screen: Bright color coded LEDs and built-in speaker provide both visual and audible tone for readiness verification <span class="a-text-bold">Circuit Test:</span> Used for diagnosing the vehicle electrical system, including DC or AC voltage test, continuity test, and current test. <span class="a-text-bold">Starting Test</span>: Measure the cranking voltage to have a test of vehicles starting system which is commonly referred to as the cranking system to confirm its functioning properly, or provide valuable diagnostic information for isolating a problem in the system. <span class="a-text-bold">Charging Systems Test:</span> Ensures the battery will remain charged to; starts the vehicle and powers the accessories while its running; tests the integrity of the 12-volt charging system periodically.