Here's what you should do:
1. Don't panic, but don't ignore it: The light doesn't necessarily mean a catastrophic failure. However, it does mean something needs attention.
2. Get the code read: You need to get the diagnostic trouble code (DTC) read from your car's computer. This code tells you *what* the car's computer detected. You have several options:
* Auto parts store: Most auto parts stores (like AutoZone, Advance Auto Parts, etc.) will read the code for free.
* Mechanic: A mechanic will read the code and can often diagnose the problem based on the code and a visual inspection. This is usually the best option as they can properly assess the issue.
* OBD-II scanner: You can purchase a relatively inexpensive OBD-II scanner for your own use. These plug into your car's OBD-II port (usually under the dashboard) and display the trouble code(s). However, interpreting the code might still require some knowledge.
3. Address the problem: Once you know the code, you can research what it means (many online resources are available) or take it to a mechanic for repair. The problem could be anything from a loose gas cap to a more serious issue requiring significant repair. Ignoring the problem could lead to bigger, more expensive repairs down the line.
4. Don't just reset the light: Simply clearing the code without fixing the underlying problem will only temporarily turn off the light; the light will come back on as soon as the problem reoccurs.
In short, get the code read and then address the underlying problem. Don't just rely on resetting a light that's not related to the "Service Engine Soon" warning.