Road Departure Mitigation System Problem Causes And Fixes

Do you find yourself dealing with a road departure mitigation system problem?

It is most definitely not fun to deal with such a problem. After all, the last thing you want is to encounter an issue with your road departure mitigation system. 

In case this is something you are currently dealing with, you are at the right place. Today, we will cover the different causes of this problem, some fixes you can try, and other key details you should know.

road departure mitigation system problem

Road Departure Mitigation System Problem

First of all, a road departure mitigation system are alerts that help you when your car crosses over the detected lane parks or leave the roadway while you are driving at a speed of 45 to 90 mph. This is when the crossing over is done unintentionally. This way, the chances of an accident are reduced.

In case your car gets near the detected markings and your turn signal is not activated, the road departure mitigation system also adds in a steering torque. What this does is it alerts you by sending rapid vibrations through your steering wheel. By doing so, you can easily realize that you are shifting on the lane and keep you within the lane detected.

As for the visual alert, this message shows up on your driver information interface. When the steering input has been detected as insufficient in maintaining the car on the road, braking may be applied.

Moreover, this system cancels out any assisting operations whenever you turn your steering wheel. This helps with preventing you from crossing over the detected lane marking on the road. But if this system ends up operating many times and not being able to detect a response from you, it continues to beep as a way of alerting you.

But as with any assistance systems, there are limitations to the road departure mitigation system. As an example, when you rely only on this system, and you do not apply proper caution when driving, it can still lead to an accident. Thus, you should realize that you are responsible for your actions and in making sure that your car stays within the reasonable driving lane as much as possible.

Furthermore, this system is only capable of alerting you whenever it detects a lane drift, as long as there is no turn signal activated. With that being said, it is unable to detect any lane markings, as well as roadway or lane departures.

There is also the likelihood that it is only accurate when the weather is good, as well as depending on the lane marker conditions and the speed of your vehicle.  Hence, you should first and foremost be more cautious on the road and not rely purely on the RDM system.

So what are the reasons behind a road departure mitigation system problem anyway? There are a few causes for this issue including:

1. Obstructions to the radar sensors

For the most part, the typical cause of a road departure mitigation system problem is an obstruction to the radar sensors. Naturally, when these are blocked, the RDM won’t be able to detect any problem and won’t send you any alert. This is why during winter, be sure to get rid of snow buildup on the sensors that can prevent these from working efficiently. 

2. Inclement weather and bad road condition

As we have mentioned above, you want to make sure that there are no blockages to the sensors. These include fog, rain, or snow. This is why when there is a problem with detecting the vehicle or the lane ahead, then the RDM system will be less efficient, as well. 

Another possible reason for the inefficiency and inaccuracy of the RDM system is when the roads are bad. Winding roads and any serious road issues can stop the sensors from effectively detecting lane markings.

3. Your speed.

Are you driving at a very low speed? If so, this can be preventing the road departure mitigation system from working as it should. You need to maintain the recommended speed to make sure that the sensors work properly. 

So what can you do about these issues? The quickest and easiest way to fix this problem is by doing a reset to the sensor. This is usually the first step before you take your vehicle to the auto mechanic. 

To reset, simply press and hold the button to your main sensing system. This should disable any sensor features. Afterwards, you can press it a second time, which will then restore the features.

Additional Points To Remember

road departure mitigation system problem

Your road departure mitigation system allows you to drive safely by keeping you within your lane markings. In case you drift farther away or leave the road, you will feel a vibration on your steering wheel to alert you. This is why it helps to keep you safe on the road and keeps you in line – literally!

You should see a lane departure message show up on your dashboard. In case it senses you have not returned to the appropriate lane, then the system applies brakes to prevent accidents. 

However, if this function does not work, a reset of the system is always worth a try. But if after trying everything you can, the system  still fails to work properly, then it is always good to take it to your mechanic and have it checked more thoroughly. 

Now, with the complexities of this technology, it may as well be better to get the sensor replaced. If you want to replace this radar sensor, it can set you back around $850 to as much as $2,050. This is the typical price for the rear bumper sensor. However, the front radar sensor is more expensive at about $900 to $1300. 


There are many reasons why the road departure mitigation system problem may occur. Whether this is due to an obstruction or failing sensors, it is always best to get these components checked by a specialist to have the issue remedied appropriately.

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