To find out what the problem is, you need to get the diagnostic trouble codes (DTCs) read. Here are your options:
* OBD-II Scanner: The most common and affordable method. You can buy a relatively inexpensive OBD-II scanner at most auto parts stores. These scanners plug into a port (usually under the dashboard) and read the codes. Many scanners will also give you a description of the code.
* Auto Parts Store: Many auto parts stores will read the codes for free. They'll likely give you a printout of the code(s) and might offer suggestions, but keep in mind that they are trying to sell you parts. Get a second opinion if they recommend expensive repairs.
* Mechanic: A mechanic will be able to diagnose the problem accurately and repair it. This is the most reliable but often most expensive method.
Before you do anything:
* Don't panic. While it's important to address the issue, many check engine lights are caused by relatively minor problems.
* Note any changes in your car's performance. Is it running rough? Is the gas mileage down? Is there any unusual noise or smell? This information can be helpful to a mechanic.
Once you have the diagnostic trouble codes, you can search online (e.g., searching "OBD-II code P0171" if that's your code) to get more information about the potential cause. However, remember online information is not a replacement for professional diagnosis.
Ignoring a check engine light can lead to more serious (and expensive) damage to your car. Get it checked out as soon as possible.
