Average car owners can save money and develop safer driving habits by using their car’s On-Board Diagnostic II (OBD-II) system, using scan tools that easily plug into your car’s OBD-II port — usually located under the steering wheel. Here are five things you can do by plugging into the OBD-II port:

Read check-engine light codes

The most basic scan tools, which you can find for about $10 to $20, read the engine code that has triggered the check-engine light to come on. This can tell you whether the problem is minor and can be fixed later, or whether it’s serious and needs immediate attention. For example, search online for the code P0456, you will see that it’s caused by a small evaporative leak, which often just means the gas cap is loose.

Clear your check-engine light

With a scan tool that costs about $35, you can clear a check-engine light yourself.

This helps owners with older cars, which might chronically throw out check-engine lights for minor problems. (However, since pre-1997 vehicles used an earlier version of the diagnostic system, they could require an OBD-I device.)

Keep in mind, however, that even if you turn off the light, you will still need to fix the underlying problem.

Track your car and driving

Some OBD-II devices track and record your fuel economy, which could help you change your driving habits and save money on gas.

Moving up into the $100 range, OBD-II devices provide an array of functions. Many of these pocket-size plug-ins send information to your smartphone via Bluetooth or Wi-Fi. Many devices log your trips — a nice feature for business people expensing their miles.

Teach your teenager to drive

Ever wonder where your teenage driver goes in your car? Now with certain devices — ranging from about $80 to $150 — you can track and monitor your teenagers’ driving activity, and help them become safer drivers. Although some require a subscription fee, such trackers provide tips and educational information for teenage drivers and issue driving reports.

 

Boost your car’s performance

Certain OBD-II enabled devices include computer programs that allow you to change your car’s operating system for better performance. For driving enthusiasts, these OBD-II enabled devices — which can cost a few hundred to more than a thousand dollars — offer a more-sophisticated assessment of your vehicle’s health and let you tailor its performance.