Check engine light flashes and traction control light on. Causes

Does your heart skip a beat when your engine light comes on while you are driving? Well, you are not alone. The engine light can be an indication of a major problem that cannot be ignored until it has been fixed.

Therefore, if you see your engine light flashing and your traction control light is on at the same time, the most common causes are related to a faulty traction control system and its malfunction due to road conditions.

Typically, when you see more than one warning light on your car’s dashboard, there is usually more than one reason why this is happening.

If you do your research or read the related information in your car’s owner’s manual, here are some of the causes of these lights flashing intermittently or staying on.

  • The system is beginning to deteriorate or it is hardcoded
  • Faulty wheel speed Sensors
  • Potential loss of traction in the rain or icy roads
  • Malfunctioning of the traction control system
  • Loss of control of one or more wheels
  • A badly misfiring engine or a harsh transmission shift

As you can see, there are many different reasons why these dashboard symbols light up at the same time in the dashboard, and they need to be investigated.

Also, because these are warning lights that come on for your safety, they should not be ignored. In fact, for the safety of any passengers that are presently in your vehicle, you should consult with a mechanic to identify the problem before you continue to drive.

It is also important to note that the presence of both warning lights in the car’s dashboard (engine light and traction control light) at the same time may make these issues a little more difficult to analyze.

This is because you will need an explanation of why both lights have been triggered. For instance, are these issues interrelated? Or, should these problems be isolated and diagnosed? Either way, you need a repair solution that will take care of both lights before you can drive comfortably again.

How to diagnose the problem of these two error lights?

Fortunately, because the newer vehicles are run and operated by a variety of different computer programs and sensors, these diagnoses can be made a lot easier without tinkering around physically under the hood.

Instead, you or your mechanic can use an OBD2 scanner or other tools to find the exact error. For instance, if the OBD2 scanner shows a P0602 code, it usually means the problem is due to decreased engine performance. And, here are two of the codes that may show when the traction control light is on.

Error Codes

  • PO856 OBD-II Trouble Code – Traction Control Input Signal – defective on and off switch or defective connectors
  • PO858 OBD-II Trouble Code – Traction Control Input Signal – defective on and off switch or damaged wiring

Therefore, if a mechanic is diagnosing the engine light and traction control lights issues, they may use the OBD2 scanner to diagnose the problems before these problems can be repaired correctly.

Does bad traction control cause problems for the engine?

If your vehicle’s traction is cut and the wheels begin to slip, this could cause problems with your engine’s power as well as other functions like its acceleration. This is primarily because your system cuts power to your vehicle’s wheels while you are driving up slippery and steep hills.

Does the check engine light is on/flashing always when the traction control light is on?

To answer this question correctly, car owners need to read the owner’s manual that comes along with their vehicle.

These manuals are written with vehicle-specific operations in mind and have the guidelines and instructions that are needed to explain the system’s operations for its traction control features.

For instance, an owner of a Toyota or a Honda vehicle may read the information that covers when the engine light and the traction control illuminate.

The manual that the drivers use will also explain exactly what it means when these lights stay on or blink.

Also, it is worth mentioning that newer car models will show the check engine light at the same along with other warning lights to inform the driver that the issue is serious and needs to be checked.

The cost to fix the possible causes with check engine light and traction control light

The cost of fixing these issues usually vary greatly based on the repairs that will need to be done. You may also find different estimates and quotes from the mechanic that will be performing the work, and supplying the parts for these jobs.

For instance, per RepairPal’s site, the average cost of replacing a traction control can range from about $37 to $47 per hour. However, you should also know that the taxes, fees, and location differentials are usually not included in these quotes.

So, you will need to take these factors into account before you approve the work. And, if you want the best price, you shop around for an affordable mechanic shop that offers this specialized expertise.


What causes the check engine light to flash and traction control light to stay on, is a common question that drivers ask today. Since the traction control light is a part of the newer and most updated sensor technologies, people are always looking for information that explains how these warning signals work.

Also, because the engine warning light and the traction control lights may appear at the same time, drivers need to know what these warning signs mean.

Typically, when a driver is researching the cause of these lights, they may find several different reasons why they are being alerted.

This is especially true for anyone who is presently driving on roads that are either extremely wet or icy. Whatever the case or situation, every driver needs to know what these warning lights mean.

Finding the meaning of these codes is not difficult because of tools like the OBD2 scanner. The OBD2 scanner is very instrumental in providing the exact code for that particular problem.

And, these special codes can be used to find out what types of repairs need to be performed to correct these warning lights. The cost of these repairs can also differ in price ranges dramatically based on the type of problem that has to be repaired.

Scroll to Top