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While out driving today, I got a live demo of the collision avoidance systems on this car. It happened so fast I'm not sure if I can accurately recall exactly what happened. I was driving on a 4 lane road with a center turn lane probably around 55mph which is the speed limit. Cruse control was off. I was in the left lane and had cars in front of me, behind me, and beside me in the right line but they were not immediately to my right meaning I had room to move over if I had to. A pickup truck turned left onto the road in the direction I was traveling from the opposite side of the road. He did so pretty aggressively and at a sharp angle looking like he was going to run into me. I began to take evasive action by hitting the brake and moving to the right when the car seemed to take the same action but much more aggressively. All at once the car...
- Applied the break hard to a point the tires briefly locked.
- Tightened the seat belt very tight.
- Turned the steering wheel right then left to swerve around the truck potentially entering my lane. I likely went a few feet into the right lane as a result.
- I am not sure but it felt like I was pushed towards the center console since any impact would have been on my left side. Perhaps the PRE-SAFE Impulse Side feature in action.
- Gave an audible alert similar to what you get when backing out of a parking spot and a car is coming.
I'm not even sure I applied the brake or swerved right on my own or the car did it all. The truck never did jump in front of me but he did squeeze in behind me and in front of another truck. It all happened in maybe 1/4 of a second and the car never felt like it lost control but it felt like there were two drivers for that short period of time. I was able to immediately get back on the gas to continue with the flow of traffic like nothing happened. Checking my mirrors, I did not see a ripple effect of another car seeing me brake and swerve and needing to take action to avoid me. My speed was only briefly interrupted and I was back to going with the flow of traffic in less than a second. When I got home I pulled the USB drive to see if the dashcam captured the event but sadly it did not. There were no recordings for the past two days likely to due a separate issue I won't get into now.
As far as the car doing what it did, I have mixed feelings. I could have avoided the pickup truck on my own even if it pulled into my lane. But the car decided to take action that caught me by surprise. If the truck had pulled into my lane, the action the car took would have likely helped to prevent an accident. Thinking back, it may have actually just magnified my own inputs since I was already applying the brake and beginning to swerve, but just not as aggressive as the car did on its own. It was very strange!
If you have the Driver Assistance Package, then you experienced the Evasive Steering Assist. As you said, it amplified what you already did. While in this description it says pedestrians, my understanding is that it is not limited to pedestrians in your path. The system assists you whenever you perform an evasive maneuver.
I've seen similar behavior where the collision avoidance system might be reacting to faulty sensor inputs or software glitches. It's possible that the radar or camera modules are providing inconsistent data, causing the ADAS to engage unexpectedly. Another potential issue could be with the vehicle's CAN bus communications, leading to erratic signals being sent to the control modules. Additionally, a malfunction in the steering or braking actuators could result in the system taking over more aggressively than intended. To properly diagnose this, you should retrieve fault codes from the ADAS Control Module, Body Control Module (BCM), and the Engine Control Unit (ECU). I recommend using a full system scanner like youcanic’s full system scanner, which effectively diagnoses all system modules. Be cautious with generic OBD2 scanners such as the Autel AutoLink AL319, as they typically only scan engine-related codes and won’t detect issues in other control modules. If you’re not comfortable handling this yourself, taking the vehicle to a mechanic with the right equipment is your best bet. I
I don't think the collision avoidance systems were faulty in this case. The system reacted quickly and appropriately based on the situation. It was just unexpected from me as I have not had a car do that before. I posted my story about it to share the experience and not to indicate there was some type of malfunction.
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