How to Reset Check Engine Light

Your car’s check engine light serves an important purpose, but once it illuminates, it can be difficult to get it to turn back off – even after you’ve had your car inspected and serviced. Sometimes, there might not even be anything actually wrong with your vehicle, but the check engine light was triggered and has now become quite the annoyance during your daily Cincinnati commute. In the guide below, we provide simple solutions for how to reset a check engine light. For service related to the check engine light (and all other car components), trust our team at Mercedes-Benz of West Chester. Our experts can inspect your vehicle, diagnose it, and provide the Mercedes-Benz service your model needs to run smoothly.

Steps for a Mercedes Check Engine Light Reset

1. Determine Whether There’s An Issue to Resolve

First things first: before you reset your check engine light, you need to have your vehicle inspected to determine whether there’s a problem to address. Visit the Mercedes-Benz of West Chester Service Center to have diagnostics run on your vehicle. If an issue is discovered, it’s recommended that you schedule a service appointment to have it resolved without delay. The longer you wait, the bigger (and costlier) the problem can become.

2. Try Disconnecting the Negative Battery Cable

If your service technician determines that there is no service issue with your vehicle, your best option is probably to reset the check engine light manually. Car owners who don’t spend much time under the hood of their car may be nervous to try this method, but it’s easier to carry out than you might imagine! Of course, you can always schedule an appointment with Mercedes-Benz of West Chester to have our expert service techs handle everything, too.

How to perform a Mercedes check engine light reset without scanner:

  • Make sure your car is turned off and cooled down before you begin. For your safety, it’s smart to wear cotton gloves and plastic goggles during this process.
  • Pop the hood and locate the negative terminal on the battery. Usually, it has a black cap and a negative (–) symbol . For reference, the positive cap (which you will not be using) is red and will have a positive (+) symbol.
  • Using a wrench, loosen the nut on the negative terminal. Then, pull the negative connector away from the battery and leave it moved aside for 30 to 60 seconds.
  • After 30 to 60 seconds have passed, you can reconnect the negative cable and use your wrench to tighten it up again.

3. Try The Gas Cap Trick

You can usually reset the check engine light successfully following the previous method, but in the event that it doesn’t work, there’s a much simpler process to try.  Sometimes, a loosened or cracked gas cap is the culprit of a triggered check engine light. This typically happens because of the fumes that are released.

Simply remove your gas cap and put it back in place, then turn your car on to check if the engine light has reset. 

How long until check engine light resets after loose gas cap?

Once you screw the gas cap into place and restart your car, the check engine light may already be off. If not, it might take a few cycles of turning your car off and on to make it reset. In some cases, it helps to drive around for a few miles, too.

4. Schedule Service at Mercedes-Benz of West Chester for More Help

If you just can’t get your check engine light to reset, the service pros at Mercedes-Benz of West Chester can help. Our expertly trained technicians can resolve the issue in a timely manner, and when you utilize our service specials, you can enjoy great savings in the process! With any questions, please contact us online or call us at (513) 450-9099.