Check Engine Light Flashing and Traction Control Light On

I can completely relate to that heart-sinking feeling when your check engine light starts flashing and the traction control light decides to join the party. It’s a scenario that can make even the most experienced drivers uneasy. 

But, after dealing with it a few times, I’ve learned how to handle it, and I’m here to help you understand what might be going on and how to approach it. 

When the check engine light flashes and the traction control light comes on, it indicates a severe engine misfire. The problem could range from low tire pressure to issues with spark plugs, vacuum hoses, or heat gasket leakage. Whichever the case, you should not ignore these warning lights, as they could affect your safety. 

check engine light flashing and traction control light on

What is Check Engine Light?

The check engine light is a warning light on a vehicle’s dashboard. As part of the onboard diagnostics system, it is there to alert you when there is a potential issue or malfunction in one of the vehicle’s systems. In essence, the CEL serves as an early warning system and prompts you to have the car inspected and diagnosed to prevent further damage and maintain optimal performance.

Common Causes of the CEL Turning On

From my personal experiences and insights, I can share several common causes for the check engine light turning on in vehicles. These issues can vary in severity, but they all require attention. Here are some of the typical culprits:

  •  A loose or improperly sealed gas cap can trigger it. It’s one of the easiest issues to address and should always be checked first.
  • When an oxygen sensor malfunctions, it can lead to reduced fuel efficiency and increased emissions and trigger CEL.
  • It can be triggered by issues with the catalytic converter, such as a failing or damaged unit. This can be a more costly repair, by the way.
  • The MAF sensor measures the air entering the engine. If it malfunctions, it can impact engine performance and trigger the CEL.
  • Worn-out spark plugs or ignition system problems can lead to misfires and then affect engine performance, prompting the CEL.
  • Leaks in the vacuum lines or hoses can disrupt the engine’s air-fuel ratio and trigger the CEL.
  • It could arise as a result of a malfunctioning thermostat. 
  • Issues with the EGR valve can affect emissions and engine performance. 
  • Problems with the transmission, such as slipping or shifting issues. 
  • Malfunctioning of various sensors throughout the vehicle, such as the crankshaft position sensor or camshaft position sensor.

Does Check Engine Light Indicate an Issue?

Yes, the check engine light does indicate an issue with your vehicle. The issue can range from something relatively minor, like a loose gas cap, to more significant problems with the engine, transmission, or emissions systems. 

Ignoring the check engine light could lead to more extensive and costly repairs down the road, so it’s essential to address it promptly to determine the specific problem and take appropriate action.

What Is Traction Control Light?

The traction control light is like a watchful guardian on your car’s dashboard, and it’s there to alert you when something might be amiss with your vehicle’s traction control system. This system is your trusty sidekick, especially when driving on challenging road surfaces like snow, ice, or anything less than perfect. Its job? To make sure you stay in control, even if one or more of your wheels decide to slip and slide.

The traction control light can have different meanings depending on the situation. Here are some possible scenarios:

  • The light flashes on and off when you’re driving. This means that the traction control system is working to prevent your wheels from slipping and maintain your stability on the road. You don’t need to worry about this, as it indicates that the system is functioning properly.
  • When the light stays on after you start the engine, this means that there is a problem with the traction control system, and it may not work when you need it. You should get your car checked by a professional mechanic as soon as possible to diagnose and fix the issue
  • If the light is off when you start the engine, but comes on randomly while driving. This means that there is a serious fault with the traction control system, and it may cause your brakes to apply randomly or your engine to lose power. You should stop driving your car immediately and get it towed to a repair shop for safety reasons.

Why Is My Traction Light On?

Some of the common causes of the traction control light coming on are:

  • There is an issue with the wheel speed sensor that measures the speed of each wheel and sends it to the traction control system.
  • The yaw sensor that detects the angle of your car’s rotation and helps with stability control is faulty.
  • The traction control light can come on when there is a fault with the steering angle sensor responsible for the positioning of your steering wheel, which helps with steering correction.
  • A problem with the anti-lock braking system, which works together with the traction control system to prevent your wheels from locking up.

Why Is My Check Engine Light Flashing and Traction Control Light on Simultaneously?

There are many possible causes for the check engine light and traction control light to come on at the same time. Some of the common ones are:

  • Due to a misfire in one or more of the cylinders as a result of faulty spark plugs, ignition coils, fuel injectors, or other components.
  • It could result from a malfunctioning traction control system caused by a bad wheel speed sensor, steering angle sensor, steering rack, or programming issues.
  • As a result of a dysfunctional vehicle speed sensor affecting both the engine and the traction control system.

To diagnose the exact problem, you need to scan your car’s computer for trouble codes using an OBD2 scanner. The codes will tell you what part of the system is malfunctioning and what needs to be fixed or replaced. You can either do this yourself if you have the scanner and the skills or take your car to a professional mechanic for a proper diagnosis and repair.

Potential Consequences of Having the Check Engine Light and Traction Control Light on Simultaneously

Take it from an experienced driver: When you see both the check engine light and the traction control light illuminated at the same time, it’s like your car’s way of waving a caution flag. There are indeed safety implications and potential consequences you should be aware of:

1. Reduced Traction

The Traction Control System won’t be fully operational when its light is on, which means you might experience reduced traction, especially on slippery or uneven roads. This can affect your ability to control the vehicle during acceleration or turns.

2. Engine Performance Reduces

The Check Engine Light indicates an issue with the engine or its components. Depending on the problem, your engine may not perform optimally, which can impact your ability to accelerate or maintain speed when needed.

3. Fuel Efficiency is Greatly affected

Engine problems often lead to reduced fuel efficiency. You might find yourself making more frequent trips to the gas station and spending more on fuel.

4. Engine Produces More Emission

A malfunctioning engine can produce higher emissions, which is not only bad for the environment but might also result in a failed emissions test if required for vehicle registration.

5. You Can Lose Control of the Brakes

In some cases, the issues causing both lights to come on can affect vehicle safety systems. This includes aspects like stability control and antilock brakes, which rely on data from the engine and TCS. Any disruption here can potentially compromise safety.

6. It can trigger further damages

Ignoring these warning lights can lead to more significant and expensive issues over time. What starts as a minor problem can escalate if not addressed promptly.

In some areas, driving with the CEL illuminated may be a violation of local regulations, leading to fines or penalties.

How To Fix Traction Control Light And Check Engine Light On?

There are different ways to reset or fix these lights, depending on the cause and severity of the problem. Here are some possible methods:

1. Use an On-Board Diagnostic (OBD2)

An OBD2 scan tool is a device that can connect to the diagnostic link connector (DLC) of your vehicle and display the codes on a screen. To use the scan tool, follow these steps:

    1. Locate the DLC under the dashboard, near the steering wheel.

    2. Plug the scan tool into the DLC and turn on the ignition, but do not start the engine.

    3. Follow the instructions on the scan tool screen to read the codes.

    4. Write down the codes and look up their meanings online or in a manual.

    5. Follow the instructions on the scan tool screen to clear the codes.

    6. Turn off the ignition and unplug the scan tool.

    7. Start the engine and check if the lights are off.

2. Drive Your Vehicle for a Few Minutes after Reconnecting or Installing a New Battery

Sometimes, the traction control light and the check engine light may come on after you disconnect or replace your battery, because the vehicle’s computer needs to relearn some parameters. To reset the lights, you need to drive your vehicle for a while, preferably on different road conditions and speeds, until the computer adjusts itself.

Problems with the wheel speed sensor, steering angle sensor, battery, wiring, fuses, brake fluid, or gas cap can cause the traction control light and the check engine light to stay on or flash randomly. You may need to inspect, clean, replace, or tighten these components to fix the lights. If you are not sure how to do this, you may need to consult a mechanic or a professional.

If none of these methods work, or if you notice any other symptoms, such as poor performance, strange noises, smoke, or leaks from your vehicle, you should take your vehicle to a mechanic as soon as possible. Driving with these lights on for a long time may damage your vehicle or compromise your safety.

Is It Safe to Drive When the Check Engine Light and Traction Control Light Are On?

Yes, it’s generally safe to drive when both the check engine light and the traction control Light are on, but it’s essential to exercise caution. While not an immediate safety risk, I will recommend you drive cautiously and avoid abrupt maneuvers.

Do not Ignore these warning lights for long to avoid safety risks over time. Therefore, have your vehicle inspected by a qualified mechanic as soon as possible to diagnose and address the issue.


Both the check engine light and the traction control light are warning lights and indicators of potential issues that can affect safety, engine performance, and emissions. The two lights can come on due to any of the reasons discussed above. 

While you can proceed to use the car with caution, I strongly recommend you have your vehicle inspected by a qualified mechanic as soon as possible. Prompt diagnosis and necessary repairs will not only keep you safe on the road but also prevent further damage and ensure your vehicle operates optimally.