Here's what you should do:
1. Get the Diagnostic Trouble Code (DTC): You need to find out *why* the light is on. This requires using an OBD-II scanner. You can:
* Buy a cheap OBD-II scanner: Many are available at auto parts stores for under $20. These will read the DTC code(s).
* Go to an auto parts store: Many stores will scan your car for free and tell you the code(s).
* Visit a mechanic: A mechanic will have the tools to read the codes and diagnose the issue.
2. Interpret the DTC: Once you have the code(s), look up their meaning online (many free resources are available). This will give you a clue about the problem. Be aware that some codes are more vague than others.
3. Address the Problem: Based on the DTC, you can try to fix the problem yourself (if you're mechanically inclined and comfortable doing so), or take your car to a mechanic. Possible causes range from something simple like a loose gas cap to more serious issues like a faulty sensor or failing component.
4. Clear the Code (After Repair): Once you've fixed the problem that triggered the CEL, you can clear the code using your OBD-II scanner. The light should stay off if the repair was successful. If it comes back on, the problem hasn't been completely resolved.
Important Considerations:
* Don't just disconnect the battery: This will temporarily clear the light, but the underlying problem will still be there and could worsen.
* Don't use a "Check Engine Light Turn-Off Tool": These are generally unreliable and won't fix the actual problem.
In short: Fixing the Check Engine Light requires identifying and fixing the root cause. Ignoring it is strongly discouraged.
