Here are your options:
* OBD-II Scanner: The most affordable option is to buy a relatively inexpensive OBD-II scanner from an auto parts store or online. These plug into your vehicle's OBD-II port (usually located under the dashboard) and will read the DTCs. Many scanners will also provide a description of the code.
* Auto Parts Store: Most auto parts stores (like AutoZone, Advance Auto Parts, etc.) offer free diagnostic code reading services. They'll plug in a scanner and tell you the code(s). Be aware that they may try to sell you parts based on the code, but you're not obligated to buy from them.
* Mechanic: A mechanic will have the most sophisticated diagnostic equipment and expertise to diagnose and repair the issue. This is the most expensive option, but often the most reliable.
Before you do anything:
* Note any other symptoms: Is the engine running rough? Is it losing power? Is the fuel economy significantly worse? Any additional information will help diagnose the problem.
* Check your gas cap: A loose or faulty gas cap can trigger the CEL. Make sure it's securely tightened. Sometimes simply tightening it will clear the light, but it's best to get the code read to be sure.
Once you have the DTC code(s), you can search online (e.g., Google the code) or consult a repair manual to get more information about the potential cause. However, without the code, it's impossible to give you a specific answer.
