On-board diagnostic (OBD) scanners plug into a port on your vehicle that’s connected to its computer system, runs a diagnostic scan, then displays error codes for detected problems. If the results are an easy fix, you just saved yourself a trip to the mechanic—and the bill that comes with it. In other cases, it can help you confirm it is time to bring your vehicle to the auto shop, helping you address problems before they become more severe (and more expensive).
Sometimes OBD ports will be concealed by a cover, making them easy to miss. Another common location for OBD ports is the vehicle’s center console on the driver’s side.