KW590 is a great upgrade from the more basic auto code scanner tool. The major function is working on vehicle engine system. Once plugged into your vehicle's 16pin OBDII DLC after starting the ignition, you can choose to diagnostic what you want to know about your cars engine system, oxygen senor, evaporative control system, etc. Then find out the problems and perhaps fix it.Works on all 1996 and later OBDII compliant US, European and Asian vehiclesEasily determines the cause of the Check Engine Light ( MIL)Retrieves generic (P0, P2, P3, and U0) and manufacturer specific (P1, P3, and U1) codesTurns off Check Engine Light (MIL), clears codes and resets monitorsDisplays DTC definitions on unit screenViews freeze frame dataDisplays monitor and I/M readiness status (emissions)Identifies pending codesEads live PCM datastreamDisplays live O2 sensor test dataGraphs data C (1996 and newer)Reads, stores & playbacks live sensor dataMemory/battery backup for off-vehicle data review and analysisSupport six languages: English, French, German, Dutch, Spanish, RussianPerforms modules present testRetrieves vehicle information (VIN, CIN and CVN)Supports CAN (Controller Area Network) and all other currentOBD-II protocolsBuilt-in OBD-II DTC lookup libraryLarge easy-to-read backlit LCD screenSoftware upgradeable via internetPrints data via PC