1. Disconnect the Battery:
This is the simplest method. It's not a true reset, but it will often clear the trouble codes.
* Steps:
1. Disconnect the negative (-) battery terminal first. Use a wrench to loosen the nut and carefully remove the cable.
2. Wait at least 30 minutes. This allows the computer's capacitors to fully discharge. Some people recommend waiting longer, even up to an hour.
3. Reconnect the negative (-) terminal. Then, start the engine.
* Important Note: This method might not clear *all* trouble codes, especially those related to more serious or persistent issues. Also, it might reset other settings, like radio presets.
2. Use an OBD-II Code Reader/Scanner:
This is the most reliable method. An OBD-II scanner allows you to read and clear trouble codes directly from the PCM. You can purchase these relatively inexpensively at most auto parts stores.
* Steps:
1. Locate the OBD-II diagnostic port. This is usually located under the dashboard, near the steering column.
2. Plug the OBD-II scanner into the port.
3. Turn the ignition key to the "ON" position (without starting the engine).
4. Follow the scanner's instructions to read and clear the trouble codes. This usually involves selecting an option to erase codes or reset the system.
* Important Note: After clearing the codes, drive the vehicle for a while to allow the PCM to relearn your driving habits and monitor for further issues. If the same codes return, you have an underlying problem that needs attention.
Which Method Should You Use?
If you only want to try a quick fix and are not concerned about accuracy of the diagnostic, the battery disconnect method is fine. However, if you want a more thorough diagnostic and a guarantee of clearing all codes, use an OBD-II scanner. This will also help you identify the cause of the problem in the first place. Addressing the underlying issue is far more important than simply clearing codes.
