Home Diagnosis and TroubleshootingDashboard Warning Lights How To Turn Off Check Engine Light – All The Different Methods!

How To Turn Off Check Engine Light – All The Different Methods!

by Jordan Harris
How To Turn Off Check Engine Light

Have you gotten the check engine light on your car and you keep asking yourself how to turn off check engine light? Well, if that is the case, then you are at the right place because there will be a lot to cover on this topic where we will learn precisely that.

Having a situation when you get a problem like this can be really frustrating. Why I’m saying this? Well, I’m saying this because having a check engine is something that nobody wants, and removing it from the car could be a real pain and can cost you hundreds of dollars.

This is why you need to come prepared for these types of situations and learn more about how you can quickly remove this light from the cluster and call it a day. Sometimes the check engine light doesn’t have a purpose, it’s just there to annoy us and ruin our day. But how to turn off check engine light? Well, we will get to that later on in this article.

The first thing that we will cover will be a small introduction to car diagnostics and learn more about the check engine light meaning and the codes that you will probably get when you are dealing with a problem like this, then we will move on to the reasons for check engine light and how to diagnose it the right way. So, if you want to learn more, please follow along.

Introduction To Car Diagnostics

Now before we dive into the check engine light meaning and the DTC codes. Let’s first learn more about the basics of car diagnostics. Knowing the basics will help you a ton when it comes to diagnosing and fixing a problem with your car. So, if you are one of those people that need a little bit of introduction, please follow along.

What is important for you in this situation is to understand the basics. When we talk about the basics we mean how everything works and how it is connected.

We live in modern times and not in the 20th century when cars were a lot simpler. Back in the day a mechanic would only tweak up your carburetor then do some tweaks on the valves and call it a day. It was that simple.

Nowadays everything is computerized and regulated through the main computer, also known as an ECM or PCM. This computer basically gets all the data from the sensors that are placed on the engine. And trust me, there are a ton of these sensors and a ton of ways in which your car can fail.

So, it is of utmost priority for you to understand how diagnostics is done and the tools you will need to get the input from the computer. And for this, you will need to get an OBD2 scanner tool. With this tool, you will be able to read all of the different codes that your car makes and then based on this input decide which components to check and bench test. But how to turn off check engine light? We will get to that in a bit.

Check Engine Light Meaning

Now before we dive deeper and start learning how to turn off check engine light, let’s first cover some of the basics when it comes to this topic. And that’s what the check engine light means in general? Let’s elaborate.

Well, the meaning of this light can be really different from situation to situation. When the light turns on, you just cannot know why it is there in the first place.

A ton of people are completely confused and freaked out when they see this light. Some people are even uninterested and don’t want to fix the problem at all and they just pretend like the light is not there.

How To Turn Off Check Engine Light

And frankly, these are two wrong approaches to this problem. Why I’m saying this? Well, I’m saying this because you have an indication of a problem. You need to be really aware of it and then move on to solve the issue.

If you are passive or you are too scared of it, you will fail to do so. So, it is your priority to make sure that you learn the meaning of this light and diagnose the problem.

For this problem to get diagnosed as we mentioned, you will be needing an OBD2 scanner tool. With this tool, you will get access to the OBD2 port of your car.

Every car has this port and you should find yours first before you jump in diagnosing. Because if you don’t locate this port, you will not be able to plug in the scanner. But how to turn off check engine light? We will get to that in a bit.

Check Engine Light Codes

Now before we learn how to turn off the check engine light, let’s take a look at the check engine light codes and try to understand them more.

As you probably know, whenever you get a check engine there are probably a few codes that are waiting for you to diagnose them.

Just turn on the scanner and let it scan the car for codes. Then based on the input you get from the car and the codes, you can move on to diagnosing the problem.

Something worth clearing out is that different types of codes begin with different letters. For example, if you have a powertrain problem you will get a code that starts with P, if you have a body problem, you will get a code that starts with B, chassis problems are marked with C, while network communications are marked with U.

Then after the letter, you will get a four-number code. The first number in most of the cases is zero, while the other numbers that follow indicate the code more precisely. For example P0171 code.

This tells us that this is a powertrain code. More precisely that you are having a problem with the air to fuel mixture on your bank 1. So, how you can tell this information? Well, you can tell this by opening up the browser and performing deep research on the code. This way you will be able to diagnose the code really fast and understand its meaning. But how to turn off check engine light? We will get to that in a bit.

Reasons For Check Engine Light

Now before we dive into how to turn off check engine light, let’s first focus more on the reasons for check engine light. We will focus primarily on problems with the powertrain and codes that begin with the letter P.

We will go through the most common codes that you might get. So, if you are interested in learning more about this, follow along.

1. Problems With The Air To Fuel Mixture

Now before we cover how to turn off check engine light, let’s first learn more about the first type of issue that could cause a problem like this on your car and turn this light on.

The first type of issue that we would like to address is the problems with the air to fuel mixture. The air to fuel mixture should always be ideal or close to ideal. And the right measurement is about 14.7:1. This means that the mixture should be 14.7 parts of air and 1 part of fuel.

Whenever there is a problem with this mixture and for some reason, this becomes a real condition, you will get the check engine on the cluster.

What is worth noting is that there could be two conditions. A lean condition when there is too much air and too little fuel and a rich condition when there is too much fuel and too little air.

The lean condition is mostly represented through the P0171 or P0174 codes. While the rich condition is mostly represented through the P0172 and the P0175 codes.

Also, the P0170 and P0173 codes sometimes are triggered when there is a problem with the air to fuel mixture and the computer senses that it is too lean or too rich.

Overall, these are the most common OBD2 codes when you are dealing with issues like this. There could be more codes, more precisely codes concerning some sensors but based on this input you will be able to tell which of these sensors need to be checked. But how to turn off check engine light? Well, we will get to that in a bit, let’s cover the next set of codes first.

2. Misfire Problems

The second type of codes that we would like to discuss before we learn how to turn off check engine light is the situation with the engine misfires. But what are misfires in general?

Well, a misfire as its name implies is a missed combustion. This means that either the ignition of the fuel was premature or delayed. Both situations are not ideal and can lead to a misfire situation.

These misfires are represented by uneven engine work, ticking noises that come from the top of the engine bay, and also there will be pops from the exhaust pipe. Depending on how extensive this problem really is and how big of a problem it is in the first place.

When this problem happens, you will highly likely notice the light as well as codes that will indicate misfire problems. Specifically, on each bank or cylinder, they occur.

These codes usually start with the number 3 and end up with the cylinder that they affect. For example, P0300 indicates a random misfire inside of the engine. This misfire can occur on any cylinder randomly.

Then there are P0301 which indicates a misfire on cylinder number 1. Then the P0302 indicates a misfire on cylinder number 2 and so on until we reach P0308 which indicates a misfire on cylinder number 8. And that is a lot of codes.

So, if you get let’s say P0301, P0303, P0305. It means that only bank 1 cylinders are affected by this problem with the misfires. If you get even numbers, the bank 2 of the engine is the one that is affected. But how to turn off check engine light? More on that in a bit.

3. EVAP System Codes

The next set of codes that we would like to cover before we learn how to turn off check engine light is the EVAP codes.

These codes are frequently one of the most common occurrences in cars and when you find out what simple thing could cause the check engine on you will be literally pissed off. Why? Well, one of the most basic reasons for this situation can simply be a problem with the gas cap. If you forgot to tighten the gas cap, then you can expect that this light will start to haunt you. But what is the EVAP system in general?

Well, this EVAP system is an emissions system that basically has the role of collecting the evaporation from the gas tank and then redirecting these fumes into the intake and then into the combustion. It is a good system but sometimes the hoses can crack and cause you a ton of trouble down the way.

These problems with this system are known as vacuum leaks. This means that the vacuum is leaking from the system and this allows unmetered air to enter and ruin the performance of your engine.

These codes usually start at P0440 and end up with the P0455 code. So, if you have a code that starts with 4, then you know that your EVAP system has probably malfunctioned or you didn’t tighten the gas cap well. But how to turn off check engine light? Well, we will cover that in a bit after we learn more about the last set of codes.

4. Catalytic Converter Codes

The last set of codes that we would like to discuss before we learn how to turn off check engine light are the codes connected to the catalytic converter.

These codes are also very common and happen a lot in cars. So, why is this the case? Well, there are O2 sensors before and after the catalytic converters.

These sensors are constantly measuring the flow of oxygen into the exhaust and based on this measurement they make a conclusion and determine if the catalytic converter is performing as it should or not.

So, when a catalytic converter is clogged or damaged, you will highly likely get a P0420 or a P0430 code depending on which side of the car is affected by this type of engine work. Whenever you have a code like this, you just know that you have a problem that needs fixing before you learn how to turn off check engine light. But more on that in a bit.

Check Engine Light Diagnostics

Now before we dive into how to turn off check engine light, let’s focus more on how you can diagnose a check engine light.

For diagnosing this problem you will need an OBD2 scanner. Just get a good one that will work on your car. There are extremely cheap ones that do not work well on every car and they will annoy you even more.

So, look for forums for your vehicle and see what type of scanners people buy. Also, read a ton of reviews online and see which of them has the best ones.

Then after you purchased an OBD2 scanner, you can jump into diagnosing the problem. Don’t pay too much attention to the first scan and clear off the codes. Then start the car and see if the light turns on again and then scan the car for codes again.

You should focus on the trouble codes that stick. These codes are the representations of your problem. Study them one by one and see what makes sense to check first. Because if you didn’t know, some codes appear as a consequence of some other code. So, you need to turn on your diagnostics mind and try to connect the dots.

Fixing issues on your car is like solving a puzzle. You just need to know how everything is connected and works together in order to be successful at this job. But how to turn off check engine light? Well, that’s what we are going to cover next.

Check Engine Light Reset

Now before we learn how to turn off check engine light, let’s see more about the check engine light reset. How you can reset this check engine light on your car? What is the simple trick on how to turn off check engine light?

Well, there are a few options that you can try. The first option is to cross your fingers and wait so the check engine disappears on its own. Which we wouldn’t recommend.

The second option is to reset the check engine light manually. And by this, you will need to locate the battery first.

Then you should disconnect the positive terminal and wait for a few minutes. Then reconnect the cable to the terminal and start your engine.

The light should be gone because with this method you have restarted the computer of your vehicle. But what is unfortunate is that it could appear again. So, how to turn off check engine light? Let’s see more on that next.

How To Turn Off Check Engine Light With OBD2

A better way how to turn off check engine light is to learn how to turn off check engine light with an OBD2 scanner.

You can do this work with your OBD2 tool and basically reset the light on your car. In order to do so, you need to let the tool scan for codes and then clear all of the codes. Once you cleared the codes with the tool, there should be no check engine. But this will not fix your problem permanently in most cases, this is why you need to learn how to turn off check engine light permanently.

How To Turn Off Check Engine Light Permanently

But how to turn off check engine light permanently? Well, you can do this only if you sort out the problem with your car. Or if the check engine light was because of some kind of PCM error calculation.

So, whenever you get a check engine light and the codes are really illogical, then you should try and see if the PCM is any good and if you are going to have the same codes with a different PCM.

How To Turn Off Check Engine Light

This can be tricky to pull off but is essential in order to make sure that the issues are not because of a bad PCM.

Resetting the “Check Engine” Light

  1. The “check engine” light indicates an electrical or mechanical problem with your vehicle.
  2. After fixing the issue, the light may not turn off automatically.
  3. The check engine light being on can cause emissions test failure and prevent you from finding out about future problems.
  4. It is important to make sure that the light is not on because the engine still has a problem.
  5. There are four methods to reset the check engine light: driving the car, turning the car on and off three times, disconnecting and reconnecting the battery, and using an OBD code reader.
  6. Using an OBD code reader is a very effective method to reset the check engine light.
  7. An OBD code reader is required to turn off the check engine light.
  8. If the issue has been repaired and the computer has been cleared, the light should turn off soon after.
  9. A code reader can give you the error code that your car is producing, which can help troubleshoot the vehicle.
  10. If the check engine light remains on after attempting to reset it, there may be something mechanically wrong with the vehicle that needs to be fixed.

Conclusion

In this article, we have covered quite a bit when it comes to the question of how to turn off check engine light. First, we learned the basics of car diagnostics and how it is done the right way.

Then we learned the most common codes that you might come across when you are having a problem like this. Then we learned how to diagnose and how to turn off the check engine permanently.

F.A.Q

Now let’s answer some frequently asked questions.

What Does Check Engine Light Mean

The check engine light means that you have a problem with your car. This light means that computer diagnostics need to be performed on the car and then the problem is diagnosed and solved.

What To Do When Check Engine Light Comes On

When you get this light, the best would be to stop the car if you get symptoms instantly. If not, you can keep driving until you reach the gas station and see if something is going on under the hood. If not, keep driving and take your car to a shop whenever you can. Or get a scanner and scan the car by yourself.

Why Is My Check Engine Light On

There could be a ton of reasons why this could happen. Nobody will be able to tell you why is on until the car is properly diagnosed with an OBD2 scanner. So, get a scanner and scan the car to see what is causing this light.

How Long Can You Drive With Check Engine Light On

This depends on the cause of the check engine light. If it’s a small issue, you can keep driving as much as you want. But if you start to experience serious symptoms. Then you need to take your car to a shop as soon as possible.

How To Reset Check Engine Light Without Scanner

You can reset the check engine light by removing the positive terminal from your battery for a few minutes, then plug it back in and the computer should be restarted and the light will be gone.

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