Note that vehicles made before the 1990s may not have an OBD port under the dash. If they do, it may be an OBD-I port rather than an OBD-II port, so you may need a different scanner.

The OBD port has 16 small openings for pins that are lined up in 2 rows. It looks a bit like an old VGA port.

The code will be a series of letters and numbers. Record all of the codes so you can figure out what they represent and make the necessary repairs to your vehicle. {“smallUrl”:“https://www. wikihow. com/images/thumb/7/7d/Reset-a-Check-Engine-Light-Step-3Bullet1. jpg/v4-460px-Reset-a-Check-Engine-Light-Step-3Bullet1. jpg”,“bigUrl”:"/images/thumb/7/7d/Reset-a-Check-Engine-Light-Step-3Bullet1. jpg/v4-728px-Reset-a-Check-Engine-Light-Step-3Bullet1. jpg",“smallWidth”:460,“smallHeight”:345,“bigWidth”:728,“bigHeight”:546,“licensing”:"<div class="mw-parser-output">

\u00a9 2023 wikiHow, Inc. All rights reserved. wikiHow, Inc. is the copyright holder of this image under U. S. and international copyright laws. This image is not</b> licensed under the Creative Commons license applied to text content and some other images posted to the wikiHow website. This image may not be used by other entities without the express written consent of wikiHow, Inc.
\n</p>

<br />\n</p></div>"} Some scanners will define or explain the codes while others will not. If you don’t get a definition, look up the code in the owner’s manual or online.

Once the OBD system resets (which occurs after a few drive cycles or a certain number of miles, depending on the vehicle), the light will come back on if the problem has not been fixed.

Just FYI, erasing codes by disconnecting your vehicle’s battery can also clear out the memory for your radio and other onboard components.

If you don’t drive all that often, now is the perfect time to take that shopping trip where you need to go way out of town! The mechanic normally resets the computer codes before returning your car to you, but they may have simply forgotten this time. This is most common on older vehicles with more primitive computer systems.

If the check engine light begins to flash, you have an OBD-I vehicle, which might explain why you’ve had trouble turning the light off. Purchase or borrow and ODB-I scanner to reset the light. If a code pops up on your odometer, write it down and look it up online or share it with your mechanic. This is an error code and your check engine light wasn’t on by accident. [10] X Research source