The Check Engine light is on - what malfunctions does the yellow, orange or red icon on the dashboard indicate? The most common causes of inflammation of the control organs

A stubbornly flashing engine light on the dashboard can drive you crazy. On the other hand, when it turns red, it means serious trouble. Check out what the glowing engine icon means on different occasions.

On the dashboard of your car, you may see different shapes and colors of icons. Some of them you should know well - their appearance is regulated by law. Otherwise, the vehicle manufacturer decides. Checking the engine is one of the first. Remember what it means.

Car lights

All new production vehicles sold since 2001 in Europe must be equipped with self-diagnosis systems, i.e. electronic systems. They allow you to identify possible malfunctions. The indicators used in the car can be informative, warning and alarming. They don't always have to light up immediately to indicate a failure, and they don't always have to prompt you to take immediate action.

The check engine light is on - what does it mean? What failures can this portend?

One of the most important controls is the check engine light. What means? The engine warning light mainly informs about malfunctions associated with the engine itself, that is the drive. You will find it almost always in cars that have an OBD-II diagnostic connector and are responsible for correct exhaust emissions, that is, in all cars from the European market with a production date after 2000. Most often, when the indicator light comes on, it means that the electronic control unit has detected a mechanical problem. Check engine informs the driver about the need to check the operation of the drive unit, in which the controller could diagnose incorrect signals from the systems or exceed the parameters that were set at the factory.

When does the engine icon light up? Most Common Causes

Temporary engine anomalies will not cause the engine icon on the dashboard to stay on all the time. Only when these deviations persist longer will you see a Check Engine light with a characteristic engine frame on the car monitor. Momentary fluctuations may even be completely ignored by the electronic controller and will not cause the indicator to light up. So they are not a cause for concern.

The indicator is unlikely to come on when you notice that the car's power drops and fuel consumption increases. This may be a sign of mechanical damage to the engine. Unless they affect the signal of the sensors in the injection and ignition system, the self-diagnosis system will not show anything. Less important drive parameters are ignored by the on-board computer.

If an engine icon appears on the dashboard, pay close attention to it and perform the appropriate diagnostic steps. 

The check engine light comes on and off, what does that mean?

When the vehicle's on-board self-diagnosis system detects a serious engine problem, a message informing about the problem appears immediately and does not go out. If the Check Engine light turns on and off, most often the controller detects only temporary deviations from the norm.

Yellow and red engine light

The indicator light can be solid orange or yellow, or red. The red “check engine” light means a serious breakdown, to which you should respond unambiguously - refrain from continuing to move. Yellow or orange light after starting the engine indicates a situation in which there is a violation in some system. However, as long as it doesn't interfere with the operation of the vehicle, you can probably finish the trip without any problems. However, you should schedule a visit to the mechanic as soon as possible to diagnose what is going on with the car's engine.

Why is the check engine light on?

The moment you see the warning light on your dashboard, you start to wonder what could have happened to your car? Did something serious cause the alarm to go off? Is this, for example, an injection error? The reasons for this state of affairs can indeed be very different. 

The most common reasons for an engine check

If the indicator turns on and off, this may mean:

• incorrect signal from the lambda probe - often detected in gasoline engines;
• detection by the lambda probe of wear of the catalyst or damage to the particulate filter, which is associated with an increase in the level of fuel combustion and loss of power;
• broken spark plugs or wires;
• failure of the injection system;
• burnout of the ignition coil;
• failure of the flowmeter;
• blocking the turbocharger of variable geometry, which can lead to the transition of the car into emergency mode;
• Faulty EGR valve.

What will cause the check engine light to be ignored?

The consequences of underestimating the display of a red or yellow indicator can be different:

• you can observe an increasing level of fuel burning;
• your car may emit more exhaust gases;
• you will feel a decrease in the performance of the power unit;
• engine performance may be seriously affected. 

Sometimes this icon will come on in response to bad fuel or an incorrect fuel/air mixture. In cars with HBO installed, this icon appears when the installation is not done correctly and often the problem disappears after adjusting the HBO. Sometimes it is also necessary to replace misused components for an assembly.

How to determine the cause of an engine error?

The check engine icon usually won't show up for no reason, and if you can't diagnose it yourself, take it to a mechanical shop. Mechanics have the necessary equipment, incl. computer and diagnostic software to help you pinpoint faults in your vehicle. Sometimes even removing it will not remove the error from the system. This can be fixed by clearing the computer's memory. You should not perform this operation unless you have corrected the cause of the Check Engine light in the vehicle.