* Reset the computer: This is the simplest solution, and it may work if the check engine light is on due to a temporary issue. To reset the computer, disconnect the negative battery terminal for 30 seconds, then reconnect it.
* Check the gas cap: A loose or damaged gas cap can cause the check engine light to come on. Make sure the gas cap is properly tightened, and if it is damaged, replace it.
* Scan the computer for codes: If the check engine light is still on after resetting the computer and checking the gas cap, you will need to scan the computer for codes. This can be done at most auto parts stores for free. The codes will tell you what is causing the check engine light to come on, and you can then take steps to fix the problem.
* Fix the problem: Once you know what is causing the check engine light to come on, you need to fix the problem. This could involve anything from replacing a faulty sensor to repairing a major engine problem.
* Contact a mechanic: If you are unable to fix the problem yourself, you will need to contact a mechanic. They can diagnose the problem and perform the necessary repairs.
