ACC quirk turns dangerous

Sounds like you need to have the car serviced. Something is wrong with either the radar or the camera... or software?

 

KClark

Glad nothing serious happened.

Generally the best place to start with a concern is https://www.nhtsa.gov/

Other sites such as carcomplaint.com are useful to other drivers but not the official reporting path to the government agency responsible for these types of complaints.

Of course contacting Honda USA is also prudent.

Hope this helps.

 

Was it a left exit? That would explain it.

Seriously though, can you describe the situation a little more? How many lanes on the road? Which lane were you in? Was the other car in the deceleration lane? In my mind, 65 to 50 in a few seconds does not sound extreme.

Please don't contact the NHTSA until you've given Honda a chance to investigate. For all anyone knows it could have been some bird poop on the sensor.

 

If the car behind had to slam on their brakes they were too close in the first place. On exits that are just a widening of the lane until the crash barrier stripey triangle, the computer can only assume it's a wide lane. If the exiting car slows down, it'll slow down to match. Dedicated exit lanes don't have this problem. Consider staying in next lane over from exits where possible if it is a problem for your driving style. Also, remember ACC is still CC. It ain't self-driving. Keep your foot by the pedals to override when necessary.

 

We've got over 30k miles on our Clarity and I know exactly the situation you are referring to! It seems worse to me when the highway is is turning to the left with a right exit so that the Clarity is somewhat pointing towards the car that has exited and is decelerating. This is one of the exits where I have had the same situation.


geo

 

I have experienced this as well! Same exact scenario that happens every day while picking up my kid. Albeit I am usually at 40-50 due to traffic. I have concluded this happens when the exit runs too close to freeway almost like a next lane and current lane turns. The car seems to misjudge it.
Edit: I saw the example posted above...YES!!!

In addition to this a minor one is -
not allowing to take exit with out the turn indicator on. On freeways and in city, this happens sometimes though not the recommended driving behavior.

On windy roads with single lane like California-1, I just turn off the features. I have too many calls where the opposite direction car in nice bright California weather is treated as same lane due to curve of the road. The car brakes hard and it is not acceptable at 50+ speeds in my view. (happened twice in Santa Cruz mountains)

 

If Honda and the dealer tell you to go pound sand and this happens again, sure, go talk to whoever you want. Until it is investigated, engaging the NHTSA is nonsensical. First question they'll ask? Did you talk to the manufacturer? Don't be the parking ticket guy that emailed and called pretty much everyone in his town government except the mayor.

We definitely have different interpretations of extreme. Did your tires squeal? ABS come on? The guy behind you shouldn't have to slam on his brakes to slow down 15 mph in 3+ seconds. If that was the case, the guy behind you was following way too closely.

After reading the rest of the thread, I'm not even sure the car malfunctioned at all. The software/sensor combination does not like it when someone is turning/slowing to turn in front of you. It expects everyone to continue their same movement. It cannot know that the car in front of you is exiting or if the road up ahead has a sharp turn coming and the oncoming traffic is going to pass harmlessly to the side. I've had that happen to me a couple times. It is a bit jarring, but nothing I would call extreme.

Edit: Saw your last post. It sounds a little different. Definitely worth talking with Honda about it.

 

Our subaru does similar when a car in front has turned off the road. THe camera's view isn't restricted to just your lane of travel. I punch the gas pedal to tell the car to stop braking which helps to alleviate the situation.

FWIW

 

I just tap the regen paddle to disengage ACC when anything odd happens, and then drive through it.

Did you literally mean "a few seconds"? That is a long time in driving decisions. We make a lot of decisions in driving in one second or less.

 

So the ACC "car" symbol was grayed out on the dash?

I'm wondering if it wasn't ACC itself but the auto breaking system misjuding the car as a potential threat.

 

When it happens to me it's the ACC and I just hit the "go" pedal to get quickly back up to speed. The same effect has happened to me when trucks have drifted towards but not into my lane.

Although I find it annoying, I chalk it up to immature technology and live with it.

geo

 

Careful. He doesn't want to get into any pedantic lectures.

 

I have limited time driving on interstate highways in the Clarity, but I have had the car exit to the right cause the car to slow, nothing too dramatic yet though. Haven't yet had it when I was not in the same lane as the exiting car, but I can believe it is possible. Maybe your sensor is pointed slightly to the right as compared to dead ahead. Worth asking the dealer to check if they can. I think that maybe there is a setting in the setup for the "sensitivity" of this function (maybe with 3 settings)?

 

yea, I really did not want to sound that way. And, yes get it checked out.

even highly trained military pilots can fall into the trap of not staying on top of things, fly the plane, not the other way around is what the primary flight instructors always say.

There also seems to be some confusion (in general) about ACC slowing the car down, versus crash avoidance. As noted in that other thread about saved from the person flying out of the driveway, I think the crash avoidance response is quite fast, very different from ACC slowing down the car (for a "real" or "mistaken" reason, as geo says, which happens often).