Sometimes, even after problems with your car or truck engine were fixed light "Check Engine" will always remain. The computer of your car will not be able to warn you of other engine problems if the light remains on Read different methods listed here for resetting the light and choose the method that works best for you.
Things you need
Automotive diagnostic scanner
Open the hood of your vehicle and disconnect the positive and negative power leads from the battery. Turn vehicle lights on and leave the battery disconnected for at least 15 minutes. This will enable the vehicle's ability to fully flow to stimulate a full reset.
Connect an automotive diagnostic scanner to the computer of your car. Use the scanner to reset the light "Check Engine" and diagnose other problems with your car.
Request to have light "Check Engine" reset next time you get an oil change. This is normally a free service when you get an oil change.
Tips & Warnings
Resetting your car using the method "electrical drain" to reset the memory of the computer, the radio of your vehicle and other devices - you will lose valuable data.