You will need this information should you need to repair your vehicle. We highly recommend you keep a detailed record of code(s), including freeze frame data the ECU may have stored while setting them. If you've already scanned your vehicle's OBD-II computer and retrieved stored trouble codes, you may want to lookup the trouble codes before you delete them. The OBDII Scan Tool method of turning off your vehicle's check engine light only applies to 1996 & newer model vehicles. To retrieve stored trouble code(s), clear trouble code(s) and turn off the check engine light, read live streaming engine data (on some models). You may buy a scan tool at your local auto parts store. The simplest and safest way to turn off the check engine light is by using an OBD II Trouble Code Scan Tool. Perform these procedures at your own risk. We will describe the reset or 'turn light off' procedure so you may understand the OBDII emissions testing process and how the check engine light or service engine soon light apply to the emissions test. Without 'completed' emission monitors a 1996 and newer vehicle has no chance of passing the smog check.

We'd like vehicle owners to understand that by turning off the check engine or service engine soon light, essentially deleting all emissions data from your vehicle's engine control module (ECM), the smog machine will not know your vehicle has had or currently has any emissions faults AND all Emission Monitors will be erased as well. You may have already read information describing how to turn off the check engine light or service engine soon light prior to the emissions test in order to pass the smog inspection. You may turn off the check engine light using a scan tool or by disconnecting your car's, truck's, van's or SUV's battery. If you're performing this procedure in an effort to pass an emissions test when the check engine light or service engine soon light is on or illuminated, read on and in detail to learn how the check engine light reset procedure works.

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