First, it can save you a ton of money — and time. You can scan your own vehicle problems and avoid a lengthy expensive trip to a mechanic to learn that your gas cap is loose or needs to be replaced.  Diagnose the problem and fix it yourself.

Certainly, an OBD II code reader will cost you a little money up front, but the more you use it, the more you save on mechanics and high parts costs, the more the reader pays for itself.

In fact, it can pay for itself the first time you use it, depending on what the problem turns out to be.

An OBD code scanner can also help eliminate worry and surprises. If your “engine check” light keeps coming on and you find the problem is a faulty oxygen sensor, you know you won’t damage your car if keep driving it for a couple of days until you can fix it.

Most OBD scanners are easy to use. Simply plug it into the socket under the dash on any car, and begin checking. It’ll tell you if it finds problems and will display the codes. Some scanners translate the codes and others do not. If not, you can look the codes up for your vehicle online.

We have looked at actual owner/user reviews of OBD diagnostic code readers and have selected the top makes and models.

To see the results, see below. If you don’t see our reviews below, visit Best ODB Scanners and Readers.