Check Engine Light Code TipsSmog Check Santa Rosa Coupon
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    Your Computer Checks Your Vehicle

    Think of an OBD2 drive cycle as an emission control system checked by your vehicles computer and not a human.

    Your vehicles on board computer system does a better job checking smog than humans with smog machines.

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    Slow Computer

    The problem with the computer checking the smog is that it can take weeks or months. Your vehicle computer system checks everything during many different driving conditions.

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    It's Not How Long, But How You Drive

    Drive cycles are set by driving conditions and not driving length. Checking OBD2 Clearing House and Obtaining a drive cycle chart is your first step in getting the issue solved.

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    How Do Drive Cycles Get Reset

    Drive cycles get reset by someone clearing your vehicle computer data or your battery being dead.

    If your check engine light was on and someone cleared the light this will also clear the OBD2 Monitors.

    The system is designed to fail the smog for both not having the monitors incomplete or having the check engine light on. This prevents someone from getting a smog check by clearing the vehicle computer data. If your vehicle computer had the check engine light on the problem should be fixed. Otherwise you will be driving around and the light will come back on before all the monitors are set.

Hensley’s Auto is here to help you with your OBD2 Drive Cycle Problem. We are setting up this page as an open forum for discussion about this very frustrating issue. We are including links that we found to be helpful. Click here for smog check Santa Rosa information.

OBD2 Drive Cycle Charts

OBD2 Clearing House
This site is used by the EPA to communicate information to auto repair technicians. It has been funded by a grant.  OBD2 Clearing house is a link smog repair technicians use to check for manufactures drive cycle information or computer updates that may need to be done to set your vehicle drive cycles.
Link To Known Testability Issues

Smog Check Reference Guide For OBD2 Testability Issues And Vehicle Monitor Requirements.   This Guide Is Used By Smog Technicians.

A drive cycle monitor is an emission control system that is checked by the on board computer system of your vehicle. Each vehicle has different monitors that are checked.

Evaporative monitor – Checks for gas vapor leaks. bad gas cap, canister lines, bad evap sensors, and fuel tank vapor leaks.

EGR Monitor – Used to check EGR valve operation. The EGR valve is used to reduce NOX emissions.

Oxygen sensor monitor – Oxygen sensors are used to control the air fuel mixture and check catalytic converter operation.

Oxygen sensor heater monitor – Oxygen sensors have electrical heaters in them in order to warm up fast.

Catalytic converter monitor – Checks to make sure catalytic converter is working.

Air injection monitor – Air injection is used to heat the converter up faster, and continue the burn process after combustion.

Sample OBD2 Drive Cycle Chart

OBD2 Drive Cycle Chart

OBD2 Drive Cycle Chart

OBD2 Drive Cycle Help





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