What do you do if the check engine light comes on in a car?

If the check engine light comes on in your car, first check for any obvious issues, such as a loose gas cap. If everything seems normal, it's advisable to have the vehicle scanned for diagnostic trouble codes using an OBD-II scanner, which can help identify the specific problem. Depending on the severity of the issue, you may need to consult a mechanic for further diagnosis and repairs. Ignoring the light could lead to more significant problems down the line.