It is a compact code reader with the ability to view Freeze Frame Data, check I/M readiness (emissions) and monitor status. The engine scanner shows readiness status with a series of readiness monitors: continuous monitors like a misfire, fuel system, and comprehensive components monitor and non-continuous monitors like EGR system, O2 sensors, Catalyst, Evaporative System, O2 Sensor heater, Secondary air, Heated Catalyst, and A/C system. Autel MaxiScan MS309 CAN OBDII Code Reader provides DIYers easy as well as quick access to Diagnostic Trouble Codes and their definitions on all OBDII compliant vehicles sold worldwide since 1996. It includes important engine parameters such as RPM, vehicle speed, mass airflow, engine load, fuel pressure, short/long term fuel trim, engine coolant temperature and etc.

When I select 'Erase Code', even though my key is in the ignition in the 'on' position with the engine off, I still get this message: “Erase Failure. Autel MaxiScan MS309 universal OBD2 scanner can quickly scan and define vehicle diagnostic trouble codes (DTCs) because of its easy-to-use feature. Its broad compatibility and multifunctional capabilities make it a valuable addition to any mechanic's toolbox or car owner's garage. The Autel MS309 auto code reader is most useful while diagnosing continuous monitor faults like engine misfire and fuel control concerns.Quickly scan and define vehicle Diagnostic Trouble Codes (DTCs) with this easy-to-use, compact code reader with the ability to view Freeze Frame Data, check I/M Readiness (Emissions), and monitor status. And the auto scanner supports all 5 OBDII protocols: KWP2000, ISO2000, ISO9141, J1850 VPW, J1850 PWM and CAN.

While I have a large tool-truck brand bi-directional scan tool, there are times when I just need to check emissions monitors or quickly read a code.Please put the product with all of its accessories, free gifts and manuals back into its original box. This set of values is referred to as Freeze Frame Data and may include important engine parameters such as engine RPM, vehicle speed, mass airflow, engine load, fuel pressure, fuel trim value, engine coolant temperature, ignition timing advance, or closed loop status. Read more about the condition New: A brand-new, unused, unopened and undamaged item in original retail packaging (where packaging is applicable). It is a compact code reader that allows you to view Vehicle VIN, Freeze Frame Data, check I/M Readiness (Emissions), and monitor status before going for an annual SMOG CHECK. The Autel MS309 universal OBD2 scanner not only reads and clears generic codes (P0, P2, P3, and U0), but also supports manufacturer-specific codes (P1, P3, and U1), as well as pending codes.