Why Does the Engine Malfunction Light Come On in Cars?

If you are wondering why the engine fault light comes on in cars when you least expect it, and what are the reasons, we have explained it in all details for you. Even if the check engine light is on because of simple mistakes, it may sometimes be on due to problems that will cause great danger to your car.

Even though our cars are a vehicle that allows us to go where we want faster in our daily life, and sometimes we can spend time as a hobby, sometimes they can cause big problems for us. While you are traveling with your car, you may encounter an unexpected malfunction lamp on the instrument screen. Even if this lamp sometimes causes greater dangers, sometimes it has the possibility of burning even from simpler problems. If it hasn’t happened to you before, Why does the check engine light come on in cars? You may be wondering.

As we said above, the engine fault lamp can come on for dozens of reasons. It could mean something is wrong with your engine, something wrong with your transmission, or maybe a minor sensor has come loose. But no matter what, we strongly recommend you to take the necessary precautions when you are faced with the engine fault lamp. Because your car, which you use with confidence, can cause irreversible problems from even the slightest problem. If you wish, without further ado, in cars why does the engine fault light come on, the reasons What are they? Let us answer for you.

Why does the check engine light come on in cars?

First, let’s look at the colors and meanings of the check engine light:

  • Yellow check engine light
  • Red check engine light
  • Continuous flashing check engine light

Yellow check engine light:

Yellow check engine lightmeans that the engine failure is caused by a simpler problem. So, if you’re experiencing a yellow engine malfunction, it indicates that your car has enough of a problem that it can be serviced. Such engine failures may occur for simple reasons such as sensors and filters. However, if a dirty substance has come to your throttle, your car may still turn on a yellow check engine light for this reason. In such cases, you can take your car to the nearest service center and find out what kind of problems have occurred in the car with the error code.

Red check engine light:

red check engine light

If you are driving with your car red check engine light If it illuminates, pull your car to the right safely and quickly and stop. A red engine failure, as can be seen from its color, means that a critical problem has occurred in your car. If your car has already come to a point where the red engine fault lamp is on, you can understand this by the strange sounds coming from your engine or transmission along with the lamp. In such cases, you should call a roadside assistance service before you move your car.

Continuous flashing check engine light

check engine light

Check engine light is flashing indicates that there are smaller problems that may occur in the engine. Of course, these problems can lead to bigger problems later on and cause the light in your car to turn red. If you encounter a flashing check engine light in your car, you should go to a car dealership and seek professional assistance as soon as possible.

So why does the check engine light come on in cars?

Problems in the engine

engine diagnostics

If the engine fault light is on, some problems may have occurred in the engine. This fault is instant. DPF and EGR It may also say that it needs cleaning, there may be a problem with your turbo, there may be a problem with your glow plugs. In case of problems that may occur in this type of engine, you may encounter an engine fault lamp on your car’s display. You can go to a service as soon as possible and find out what is causing the problem.

Problems that may occur in the gearbox


Working with power transmission from engine gearbox The system is a very sensitive piece of hardware. If the engine fault lamp is on in your car, you may be experiencing problems with your transmission. For example, there may be a problem with your transmission gears. If it is a transmission-related problem, it is worth saying that it should be resolved as soon as possible. Because, gearbox repair and replacement is one of the automobile equipment that is quite expensive.

Problems occurring in emission parts

exhaust emission control

Your car has different parts for emission. If we need to give examples of these, we can say a few parts, especially the exhaust gas recirculation system, the catalytic converter. If a problem has occurred on the emission side of your car, you may still encounter the engine fault lamp. In exhaust emission Problems that may occur are a problem for your car, and exhaust emissions are carefully checked during regular inspections.

Problems with sensors and modules

oxygen sensor

Our cars are equipped with dozens of sensors. To these oxygen sensors, MAP There are quite a few sensors that can light an engine fault lamp at the slightest problem, including the sensors. If you are facing the yellow check engine light, you may be experiencing a problem with the sensors in your car. But of course, we would never advise you to skip saying “it’s just a sensor”. Although these sensors may seem simple from the outside, they can sometimes even prevent your car from starting.

Problems in the air fuel mixture

air fuel mixture control

If a malfunction lamp is the cause of different problems, starting with the fuel you buy for your car, in the air fuel mixture problems occurring. If your car doesn’t start or has trouble starting all at once, you may be facing a problem with the air fuel system. However, if you have noticed a decrease in throttle response and acceleration while driving with your car, you may be dealing with an air-fuel mixture problem.

Problems in the ignition system

broken down car

Problems with the ignition system can become a very critical problem in your car. For example, the occurrence of more than normal temperature in the ignition system, increased resistance and some electrical fluctuations. engine fault light may cause you to encounter The ignition system has a very important place in the engine compartment of your car. Therefore, if you do not take your car to a workshop as soon as possible, different problems may occur one after another.

As a result of problems that may occur for you, why does the engine fault light come on, the reasons What are they? We answered your questions. If you are faced with an engine fault lamp in your car, you need to fix it as soon as possible. You also need to choose the service you will take your car to for repair. Otherwise, you can find the engine of your car with no wiper fluid on the ground, with the excuse of “there is no part of this, bro”. Have you encountered the engine fault lamp problem before? Do not forget to share the reasons with us if you have encountered it.


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