How to Get Rid of the "Check Engine" Light
You've fixed the issue that made your "check engine" light turn on, but now it won't turn off! This may not be your fault. Sometimes the computer in your vehicle will need a little help to see that the issue has been resolved. I'll go over a few techniques for resetting your check engine light.
This light displays itself when the onboard computer system recognizes an electrical or mechanical problem with your vehicle. When the problem is fixed, the engine light does not always turn off. This can be annoying, cause you to fail an emissions (smog) test, and could keep you from finding out about future problems the vehicle's computer might be trying to alert you to.
Of course, it is essential to be sure that the light isn't on because your engine really does still have a problem. Try one (or more) of the following approaches to turn the light off. If it does not go off, then your engine has a problem.
4 Ways to Turn Off the "Check Engine" Light
1. Drive car and let light go off by itself.
2. Turn engine on and off three times in a row.
3. Disconnect and reconnet the battery.
4. Use an OBD code reader.
Wrench and OBD reader
1. Drive Your Car and Let the Light Go Off by Itself
The first and easiest method for clearing the check engine light is driving and time. Most onboard computers will recheck whatever problem caused the check engine light to activate multiple times. Drive your car as you normally would. If the check engine light is still on after three days, your problem may not have been fixed or you may need to try some of the methods below to reset it.
2. Turn Car On and Off Three Times
Some vehicles will automatically reset the trouble codes that caused the initial error after the vehicle is turned on and off three times in succession. To do this, insert your key into the ignition, turn the vehicle on for about a second, and then off for about a second. Repeat this two more times then drive the car as normal. Check to see if the check engine light reset.
3. Disconnect and Reconnect the Battery
You will need a wrench. Prop open the hood and use the wrench to disconnect the positive power cable to the vehicle battery. Leave the battery disconnected for at least 15 minutes. Then put your key into the ignition and turn it three times to the “ON” position. This will clear the emissions data from the vehicle memory as well as the readiness flag data.
Reconnect the positive battery cable and turn the key in the vehicle ignition. Wait one minute and the check engine light error should be gone.
Kobra OBD Code Read & Erase
4. Use an OBD Code Reader
You will need a wrench and an OBD reader. These inexpensive readers analyze and clear engine codes. I have used the Kobra OBD scanner with great success many times for this task (see picture). To perform this method, plug the reader into the OBD port of your vehicle. This port is usually located on the underside of the dash area just above the foot well. On some vehicles you'll have to remove the door on your fuse box to access this port. Once you have connected the reader, press the "enter" button to turn it on. The device will scan your engine for any error codes. Once done analyzing, the reader will display any error codes it finds. Make note of the code or codes if you wish to cross check them in the code reader's manual or online.
Now you can press the "scroll" button to find the option to erase the code. Press enter while on this option to erase the fault code.
Following these techniques will allow you to rid the annoying check engine light as well as allow for new problems to be displayed properly. Whether you choose to manually reset the on board computer by resetting the battery or by using an OBD reader, you will be able to successfully fix the error. You may use these techniques to fix the check engine light error as well as any other errors in the future should they present themselves.