What to Do When Check Engine Light Comes On?

Most car owners have little to no idea what the “check engine” light means or what to do when it comes on. However, they are essential and could save you from damaging critical car components or warn about your safety. Imagine you’re driving in your vehicle, and suddenly you notice a yellow light on your dash telling you to “Check Engine.” If you don’t know what it means, you’re not alone. Considering the number of mysterious lights on your car’s dashboard, not knowing what they all mean is understandable. The check engine light is the most important of these confusing signals, and there are numerous reasons why it could come on. Likewise, there are multiple ways to make it go away. But what exactly does the check engine light indicate? Understanding what to do when you spot the check engine light can distinguish between a major mechanical problem and a quick fix.  In this guide, you will learn about the significance of the check engine light, the types of check engine lights, and what to do when you see the lights come on.

Check Engine Light Explained

A check engine light is a warning indicator on a vehicle’s dashboard that alerts the driver to a malfunction within the vehicle’s emissions, ignition, or fuel systems. The light is also known as a “service engine soon” or “malfunction indicator lamp.” Although the light doesn’t mean you need to stop the car immediately and call a tow truck, you should still get the vehicle checked as soon as possible. The check engine light is only triggered when the onboard diagnostics (OBD) system detects a fault or a malfunction within the car system. Onboard diagnostics (OBD) systems are electronic systems built into modern vehicles to monitor and diagnose various components and systems within the car. These systems use sensors and other diagnostic equipment to gather data about the vehicle’s performance and report it to the driver or a mechanic via a diagnostic trouble code (DTC). Every car has an OBD system dating back as far as the 1980s. And they have become increasingly sophisticated over time. In the past, OBD systems were mainly used to monitor and control variables such as fuel mixture, ignition timing, and transmission shifting. However, modern OBD systems can monitor various vehicle systems and components, including the engine, transmission, brakes, and emissions control systems. OBD systems play a crucial role in helping drivers and mechanics identify and address problems with a vehicle. There are instances where the OBD may detect a problem that it cannot correct. This is when the engine light on the dashboard comes on, which signals to the driver that a vehicle problem needs to be addressed. The check engine light can indicate multiple issues. It could be a loose gas cap or a more severe malfunction, such as a faulty engine or transmission component. Meanwhile, having illuminated the check light, the OBD stores a diagnostic trouble code (DTC) in its memory, pointing out the problem’s source. The issue could be a sensor malfunction, engine misfire, and issues with the fuel or ignition systems. A DTC is a specific code corresponding to a particular malfunction or problem within the vehicle. The DTC is used to identify the source of the problem and guide the diagnosis and repair process. The DTC can be retrieved using a diagnostic scan tool, a specialized device connecting to the OBD system, and retrieving the stored codes. Usually, you may be required to contact a mechanic or repair technician to use the DTC, along with other diagnostic tests and inspections, to identify the source of the problem and determine the necessary repairs.  However, it’s worth noting that code readers are available for anyone to check. These code readers are small, portable devices that can be plugged into a vehicle’s OBD system through the diagnostic port, usually located under the dashboard on the driver’s side of the car. Once the code reader is plugged in, it can retrieve any DTCs stored in the OBD system’s memory. The code reader will display the DTCs on its screen, along with a description of the problem indicated by the code. Some code readers may also include a database of DTCs and their meanings, which can help you understand the problem indicated by the code. Code readers are a helpful tool, especially when you cannot reach a technician or desire to diagnose and address problems with your vehicles on your own. Even so, it is essential to note that code readers only provide a starting point for diagnosis and may not be able to identify all problems with the vehicle. In some cases, further diagnostic tests and inspections may be necessary to diagnose and repair the problem fully. It is recommended to have the vehicle checked by a mechanic or repair technician if the problem persists after using a code reader.

Different Kinds of Check Engine Lights

There are different types of check engine lights, and it usually depends on the car’s make or model. They are:

• Solid check engine light: A solid check engine light is a steady light on the dashboard. It indicates a problem with the vehicle that needs to be addressed.

• Flashing check engine light: A flashing check engine light is a rapidly blinking light on the dashboard. It indicates that there is a serious problem with the vehicle that needs to be addressed immediately. Driving your vehicle with a flashing check engine light can cause further damage to the car and may be dangerous.

• Intermittent check engine light: An intermittent check engine light is a light that comes on and off randomly. It may indicate a problem with the vehicle’s onboard diagnostic (OBD) system or a temporary issue that has resolved itself. It is recommended to have the car checked by a mechanic or repair technician if the check engine light is intermittent.

• Check engine light with other warning lights: In some cases, the check engine light could be accompanied by other warning lights on the dashboard. These lights may indicate specific problems with the vehicle, such as low oil pressure or a malfunction in the braking system. 

It’s important to clarify that the check engine light may come on in some car models when you turn the ignition on. And then it goes off almost immediately. This usually doesn’t mean there’s a problem with the car. Some cars switch every dashboard light on briefly as soon as the ignition is turned on. However, it may still be a good idea to get it checked if you’re unsure. In addition, the check engine light may vary in color depending on the specific issue and the vehicle’s make, model, and year. For example, in some newer cars, a flashing light may indicate a more severe problem, such as a severe engine misfire, that could result in a more costly repair if not addressed promptly.  On the other hand, a steady check engine light is usually not considered an emergency and may indicate a less severe problem. Either way, you should have your car checked by a mechanic as soon as possible.

Tips for Check Engine Lights

If you’ve spotted the check engine lights on your dashboard, there are some things you can do before calling the auto shop. Here are a few tips for dealing with the check engine light:

Look for Problems That Need Immediate Attention

Ignoring warning lights can further damage the vehicle and potentially compromise the safety of the driver and passengers. When the check engine light comes on, it is best to pull over and check for the problem to prevent further damage. Some common issues to look out for include low oil pressure, transmission problems, overheating, loose gas cap, etc. If this is the case, pull over when safe to prevent further damage.

Reduce Speed

If you are experiencing a blinking check engine light or any performance issues such as a loss of power, or strange noises, you should reduce your speed to lessen the demand on the engine. If the problem persists, you should have the vehicle checked by a mechanic or repair technician as soon as possible.

Use Any Built-in Diagnostics If You Have Them

Some newer vehicles also have built-in diagnostic tools or allow for remote diagnostics, which can help identify the problem and will enable you to schedule a service appointment. Utilizing these resources can help you address any issues with your vehicle promptly and prevent further damage.

Inspect With a Code Reader

You can use a code reader to retrieve any diagnostic trouble codes (DTCs) stored in the vehicle’s OBD system. These codes can help identify the problem and guide the repair process.

Have the Vehicle Checked By a Mechanic or Repair Technician

A mechanic or repair technician can use diagnostic trouble codes (DTCs) and other diagnostic tests to accurately diagnose and repair any issues indicated by the check engine light or other warning lights on the dashboard.  As mentioned earlier, ignoring the check engine light or failing to address the underlying problem can damage the vehicle further. Pay attention to all warning lights on your vehicle’s dashboard and have the car checked by a professional if any lights are illuminated. By doing so, you can help improve the performance and safety of your vehicle, as well as reduce emissions and fuel consumption. Consider keeping a record of the DTCs and the repair work performed. This can help track the vehicle’s health and identify any recurring problems.

Final Thoughts

In conclusion, the check engine light is an important warning indicator on your vehicle’s dashboard that alerts you to a problem within the vehicle’s emissions, ignition, or fuel systems. When the check engine light comes on, it is crucial to address the underlying problem to avoid further damage to the vehicle and ensure the safety of the driver and passengers. Some simple steps you can take when the check engine light comes on include checking the gas cap, monitoring the vehicle’s performance, and having the car inspected by a mechanic or repair technician as soon as possible. By following these steps, you can help ensure that your vehicle is running at its best and will help you avoid expensive repairs in the future. Is your car aging, and do you think it’s time to replace it? You could still get top dollar for your ride regardless of the condition. Auto Geek helps with the entire process of selling your car, from inspection and appraisal to payment. You can get an instant offer within three hours on a business day when you provide the necessary paperwork for your vehicle. Get an offer now.