Check Engine Warning Dashboard Light 1

Check Engine or Malfunction Indicator Car Dashboard Light

A check engine light, often known as a malfunction indication lamp (MIL), is a warning light used by a computerized engine management system to signal a problem. The legend engine, check engine, service engine soon, maintenance needed, emmiss maint, or a pictogram of an engine is generally seen on the instrument panel of most vehicles, and when lit, it is often an amber or red hue.

The light usually has two stages: constant (showing a small problem) and flashing (representing a major failure) (indicating a severe fault). The engine control unit records a fault code relating to the problem when the MIL is illuminated, which may be retrieved—though many types need the use of a scan tool. This warning light may signal a variety of issues, ranging from a loose gas cap to a severe engine knock.

The Most Common Reasons Your Check Engine Light Is On

With that in mind, let’s look at some of the most frequent causes of your check engine light.

1. Issues with the engine
Engine issues, of course, may cause the check engine light to illuminate. A control module uses a set of sensors to keep track of the engine’s performance. When it senses a problem, the check engine light illuminates.

2. Issues with transmission
The gearbox of your vehicle controls engine power and distributes it to the driving wheels. Because the two components are so tightly linked, a transmission issue may result in increased tailpipe emissions. As a result, if the control module senses a transmission issue, the check engine light will illuminate.

3. Issues with Emissions Equipment
There is a variety of emissions equipment aboard modern automobiles. The exhaust gas recirculation system, catalytic converter, and evaporative emissions system are just a few examples. Each jigsaw piece is engineered to reduce exhaust emissions, preserving the environment and making the world a safer place.

We won’t go through each of these components and systems in detail since there are just too many to mention. However, believe us when we tell that a problem with the emissions equipment may easily set up the check engine light.

Problems with modules and sensors (electronic powertrain controls)
Today’s powertrains are controlled by a variety of sensors and modules. The modules also interact with one another through a large data network. The check engine light may be caused by problems with sensors, modules, networks, and wiring.

5. Issues with air and fuel supply
To operate correctly, your car’s engine need the appropriate quantity of air and gasoline. The control module will most likely detect whether there is too much or too little of one or the other. After then, the gadget illuminates the check engine light.

6. Issues with the ignition system
The ignition system contains the spark plugs, coil packs, and all other components required to ignite the air/fuel combination within the engine. The control module, as you would expect, keeps an eye on the ignition system’s performance. If it identifies an issue, it will illuminate the check engine light.

5 Common Car sensors may cause the check engine light

1. Oxygen Sensor

Your engine’s efficiency is determined by the amount of oxygen it receives. However, too much or too little of it may create engine issues. The Oxygen Sensor is used in this situation. The O2 or oxygen sensor, which is usually found near the exhaust manifold, monitors the oxygen level in your exhaust and compares it to the oxygen level in the air surrounding your vehicle. This data is then utilized to establish if your engine is operating on a rich or low fuel ratio. This information is then used by the engine computer to determine pollution controls and fuel metering strategy. If your O2 sensor fails, your car may emit too much pollution or have performance problems.

Oxygen Sensor

2. Mass Air Flow Sensor

The mass airflow sensor, often known as the MAF, is one of the most important sensors in vehicles. The MAF sensor measures how much air is flowing into the engine and is positioned near the air filter. If the functioning of this sensor fails due to a malfunction, your vehicle will idle/stall or come to a full stop. Furthermore, the amount of gasoline used would be greater than normal. Furthermore, if your MAF sensor malfunctions, the check engine light will undoubtedly illuminate.

Mass airflow

3. Engine Speed Sensor

The engine speed sensor, which is linked to the crankshaft, is another essential sensor in your car. The engine speed sensor’s main job is to keep track of the crankshaft’s rotational speed so that the engine timing and fuel injection may be properly regulated. If your engine speed sensor fails, you may have issues with cruise control or your speedometer.

Engine speed sensor

4. Manifold Absolute Pressure (MAP) Sensor

The main purpose of the MAP sensor, also known as the mass air flow sensor, is to monitor the total load of the engine based on the density of air in the engine. The engine’s computer then uses this information to modify the quantity of fuel utilized in the combustion process in order to maintain the optimal fuel-to-air ratio.

MAP Sensor

5. Coolant Temperature Sensor

The Coolant Temperature Sensor (CTS) is one of your vehicle’s most important sensors, monitoring the temperature of your engine’s coolant. The data is then utilized to control the mechanisms in place to keep your engine cool. The cooling fan, for example, is one of these components. If this sensor fails, your engine will overheat, resulting in serious long-term damage.

coolant sensor

The engine computer has set a Diagnostic Trouble Code (DTC). Usually requires diagnosis with a professional scan tool.

Thank you! -Erwin

By erwincsalarda

I am Erwin Salarda, and I'm from the Philippines. I am really enthusiastic about learning new things in life, and my main interests are computers and automobiles. I willingly developed everything on my website so that I may share it with you.