How To Reset A Check Engine Light

Is your car's "check engine" light on but you're not sure how to fix or reset it? Here is a super simple guide showing you exactly how to do it.

In most cases, the warning lights on your car’s dashboard are helpful and important. However, sometimes they are simply disruptive and provide little or no benefit.

For example, you might have already addressed the issue that caused the check engine light, yet the light is still illuminated.

You have a few options, such as using an OBD-II scanner, reconnecting the battery, and more.

In this guide, we will look at multiple ways to reset a check engine light that shouldn’t be active.

We need to emphasize that you should only reset a check engine light after addressing the problem.

Failing to deal with the original issue could lead to permanent damage, which can cost thousands of dollars to fix.

A blinking check engine light indicates a very serious problem. If you see one, it is best to avoid driving your car until you are sure that the problem has been fixed.

Let’s jump in!

Table of ContentsShow

Diagnose The Problem

car check engine light on

Before you begin the process of resetting the check engine light, you should take some time to diagnose the problem.

In most cases, the issue causing the check engine light is not so serious that you must immediately stop driving your car. It is still important to discover the cause.

The easiest way to interpret a check engine light is to connect it to an OBD-II scanner/reader.

OBD-II stands for On-Board Diagnostic version 2, and it is present in every car produced from 1996 to the present day.

In the past, only mechanics had access to an OBD-II scanner or code reader. Today, you can acquire a simple code reader for only $20, while more advanced readers can cost more than a thousand dollars.

Thankfully, in most cases, you will only need to buy a cheap OBD-II reader, which will display a code corresponding to your car’s problem.

Once you have determined why the check engine light is on, you can act accordingly by either solving the issue immediately or planning to do it soon if the problem is less serious.

It is not unusual for several codes to appear which could be unrelated to the check engine light.

If the check engine light turns on and then off, the code will still be stored in the car’s memory, and you will be able to find out why it turned on, even if it was only for a split second.

How To Reset The Check Engine Light

Check Engine Light

If you have solved the problem, but the check engine light is still on, there are a few ways to reset the light and turn it off.

Use An OBD-II Scanner/Code Reader

One of the quickest and easiest fixes is to use an OBD-II scanner or code reader.

Much like diagnosing the car, all you need to do is to plug the reader into the OBD-II port and simply press “clear.”

This is the best way to do it, as it directly affects the car’s error code memory.

If the check engine light disappears for a while but soon lights up again, the initial problem has not been resolved correctly.

Drive For A While

Driving car

Sometimes the check engine light will illuminate due to a minor divergent sensor reading or something similar.

In these cases, simply driving the car for a few miles or minutes can sometimes make the light disappear.

This also applies if you have solved a previous problem but have not cleared the code for whatever reason.

This can happen because the car’s ECU “checks itself” regularly in set intervals. In other words, the problem might be resolved, but the ECU has not yet been updated.

Just ensure that there are no abnormal symptoms when driving, such as jerking acceleration, noises, bad handling, or any similar issues.

Reconnect The Battery

car mechanic replacing car battery VRLA car battery

Disconnecting the battery and leaving it for a while will reset the code memory of the car.

As with any other type of work that involves electricity and batteries, make sure you use all precautionary measures and be sure of what you are doing.

There is a simple and informative guide on wikiHow, showing you how to disconnect the battery step by step, but also how to erase error codes with an OBD-II scanner.

Restart The Car

Perhaps the most common question that any customer service agent asks is, “have you tried turning it off and on again?”.

There are often good reasons to restart a faulty device, which could also work with a car.

Some manufacturers have programmed their cars, so old codes are reset when turning the car on and off three times.

Simply start the car, let it run for a few seconds, turn off the engine, wait a few seconds, then repeat the process.


The check engine light is very important as it could indicate a serious fault somewhere in the system.

Sometimes the check engine light is nothing but a distraction, and you only want to turn it off.

We mentioned it before, but it is very important that you only get rid of the check engine light if you are sure that the issue is minor or you have fixed the problem but did not reset the codes.

There are several ways to reset a check engine light. The most reliable and one of the easiest ways is to use an OBD-II scanner or reader.

If you do not own such a device, you can buy a cheap one for $20. While a scanner has more functions, a code reader will usually be sufficient.

This is a good investment as it will be much easier to diagnose any future problem.

A check engine light can sometimes disappear when you simply drive for a while. This is because the ECU updates at regular intervals.

If the ECU checks after a while and there is no longer a problem, the check engine light will simply disappear.

When you drive, ensure there are no abnormal sounds and that the car drives smoothly.

Disconnecting and reconnecting the battery, as well as turning the car on and off a few times, can also reset the check engine light.

Whatever the cause, make sure to resolve any problems as soon as possible and follow the maintenance schedule specified by the car manufacturer.

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Bajro Muric

Bajro is an ASE-certified master technician and car enthusiast with a love for writing and teaching. He writes about anything regarding cars, from common problems and fixes to racing.