A check engine light can be annoying for several reasons. For example, it doesn’t explain what the problem is, so you’re left guessing as to whether it’s a minor or major issue. At the same time, the cost to hook your car up to a scanner can run as high as $100. It’s frustrating to be out that amount of money, especially if the “problem” is extremely minor. Fortunately, there are ways to avoid a diagnostic fee.

Buy Your Own Reader

The next time you notice auto parts on sale, consider picking up a code reader. You can use it to check your engine light codes. Prices range from about $30 to about $250. Odds are that you should do just fine with an inexpensive tool, but talk with store personnel to ensure you get the right type of reader.

The next time your check engine light comes on, connect the code scanner to your vehicle. You’ll get the diagnostic code, and multiple websites should explain the meaning of the code. However, you may have to run a test to further pinpoint the issue.

Stop By a Local Auto Parts Store

Open your my autozone smartphone app to find the closest auto parts store. Drive there for store personnel to perform a code reading completely free. Many auto parts shops do this service for no charge. It should take just a few minutes. You’ll receive a printout with the code and diagnosis, a rundown of the suspected issue and what you may want to do next. You won’t always get a definitive answer to what’s going on, but you should have a good starting point.

Going to a store is generally the best option for frugal people or folks whose check engine lights don’t come on often. If yours comes on a lot (like if you have an older car or multiple cars), you may want to buy a code reader.

Ask Your Mechanic

If you have a trustworthy mechanic and a good, longstanding relationship with him or her, it never hurts to ask for a free diagnostic. Some mechanics do this for repeat customers. As a bonus, if your car needs special attention or repairs on the spot, it’s already at the mechanic’s shop.

In general, though, car repair shops and dealerships do charge diagnostic fees.

Where to Get Other Services for Free

You can get services such as a battery test and battery charging for free at many auto parts stores (free engine light diagnostic checks too). Some stores even have tool loaner programs for consumers who like to tackle auto repairs on their own.

Take Action ASAP

Regardless of where you are when a check engine light comes on, get it looked at as soon as possible. That’s because the problem could be serious. Your best bet is usually an auto parts store unless you have a code reader and prefer to use it. If you go to a mechanic for a free check, make sure you trust the person. Some unethical technicians may mispresent the problem.