How to Reset Check Engine Light

When the check engine light illuminates on your dashboard, that’s a good time to schedule service at our Mercedes-Benz of Fairfield service center so we can address the issue and get you back on Fairfield roads. If your check engine light remains illuminated after you know you’ve diagnosed and taken care of the problem, you can consult this helpful guide to learn how to reset your check engine light right from your own Westport driveway.

First, Rule Out or Resolve Any Issues

In this guide we’ll cover how to reset your check engine light both with and without a scanner. But first, you want to be absolutely sure that the check engine light just needs a reset, and it is no longer trying to communicate an issue. If you try to reset the light when there’s a more serious underlying problem, it will come back on immediately. The presence of a check engine light can imply pertinent information, including:

• Loosened or damaged fuel cap
• Failing oxygen (O2) sensor
• Clogged or damaged catalytic converter
• Malfunctioning Mass Air Flow Sensor
• Expired or damaged spark plugs

Two Ways to Reset a Check Engine Light

The first way to reset a check engine light on your Mercedes-Benz is with a scanner. If you have one, simply plug it in, read the related codes, and press “clear” or “reset.” So long as the code issue has been resolved, it should go off.

Most Norwalk drivers don’t have an OBD II diagnostic scanner, but you can still reset a check engine light by disconnecting the negative battery cable. Here’s how to reset your check engine light safely:

1. Wear safety glasses and gloves.
2. Turn off the ignition, and open the hood.
3. Locate the battery and find the negative terminal. It is usually black and/or marked with a minus (-) sign.
4. Remove the cable from the terminal using a wrench
5. Hold the negative cable to the side for 30-60 seconds.
6. Be careful not to let the cables touch. This creates sparks.
7. If you have a friend nearby, have them engage the vehicle horn to deplete excess power from the vehicle.
8. Reconnect the negative battery cable
9. When you restart your vehicle, the check engine light should not illuminate.

Keep in mind that disconnecting the battery may also cause certain infotainment systems to reset at the same time. When in doubt, take the vehicle into our Fairfield service center and let us take care of everything.

Get More Service Tips from Mercedes-Benz of Fairfield

An understanding of basic car care can help you get more enjoyment out of all your drives through Weston! If you found this guide to how to reset a check engine light helpful, be sure to browse our other DIY car care tips as well! We are always happy to help our valued Mercedes-Benz customers feel informed about their vehicle’s health and operation. Contact us today with any questions that are on your mind!