Your vehicle's computer contains a wealth of information that it gathers from sensor on almost every system. It used to be that only shops had access to that information, but that's not the case anymore. On this edition of "Driver's Ed," we're talking about pocket scanners.
Vehicles built after 1995 have OBD-II, which stands for onboard diagnostics. There's an OBD2 port usually underneath your dashboard that you plug the scanner directly into, which allows it to talk to the computer.
The nice thing about these scanners is, if your check-engine light is on, it will tell you why. The cheaper models which you can get for under $50 will just give you the code, but they come with a manual to tell you what the code is.
Some models will actually give you a short definition of what that code means, right on the screen.
Knowing why your check-engine light is on can be helpful when you take it to the shop to get it fixed.
Another nice feature of these scanners is they have a USB port on them so you can update them as you buy newer vehicles.