Andrew Hunziker

The first couple of times this happened I didn't think much of it, but it now happens pretty regularly when I'm driving on the highway/freeway. Every once in a while when I use the adaptive cruise control my MDX stops accelerating suddenly just as I pass a car. It happens if I am in the left lane (passing lane) and going past someone on the right lane, even if I have been in the left lane for a while. It's almost as if the system thinks the car I am passing is suddenly in front of me and needs to slow down. I wonder if the sensor on the front of the car is just too sensitive? Anyone else having this issue?

andre12dbsi

I just picked up a new MDX so I haven’t been able to get it out on the highway but my 2020 RDX did exactly what you’re describing. It drove me nuts on my last road trip. I’d be passing a car and the RDX would slow down right when I got to the rear quarter panel of the car I was passing.

mrgold35

Does it do this for all the ACC range settings? I usually set my radar range at 2 bars and occasionally 1 bar for heavier hwy traffic on my 19 MDX and 18 RLX. It does the slow down thing sporadically with large semi truck going straight or if there is a slight left hand curve in the road while I'm passing in the fast lane with a vehicle in the slower lane.

andre12dbsi

That’s a good question. I always have my ACC set at the closest setting, so one bar. I’ve never tried to see if it does it with the other settings as well.

tamber877

Do you notice if the "car" appears on the cluster? hard to explain, but when you're driving, it shows your car all the time, and when it notices a car in front of you (don't need to be using cruise control for it to show a car in front of you) , it shows it...does the car you are passing show up there? that might help you figure out if it's sensing the car or something else weird is going on. I've never noticed this happen, but I always accelerate on my own when I'm passing on the left.

andre12dbsi

I did watch for this specifically and the car does not show up in the display. I was thinking it was picking up the car as being in front of me, but it doesn’t appear to…well not shown in the display at least.

Almatti

andre12dbsi, I am only speculating for I really didn't use the ACC on many occasions in my 2019 MDX , and now have the new 2022, but perhaps the Radar for the ACC is mixing signals form the ACURA WATCH suite of safety Features? Maybe a conflict with the Blind spot Monitoring ?

andre12dbsi

It could be. And to be clear, I haven’t experienced it on my ‘22 MDX…yet. The OP mentioned it on their MDX so I wanted to give my experience with my ‘20 RDX as it was a similar experience. It’s likely something with Acura’s ACC on certain vehicles.

mrgold35

I have the option of disabling ACC by pressing and holding the ACC range/distance button for a few seconds (turns it into regular old CC). It works for my 11 MDX, 18 RLX, and 19 MDX. Not sure if that is still the procedure for the +22 MDXs if ACC is too sensitive.

Andrew Hunziker

My findings are the same as Andre. The car I am passing is not showing up on my display/cluster. I have also had it happen on perfectly straight roads, not just on curving roads. I think Almatti is correct, where there is some conflict with the blind spot monitoring. My dashboard doesn't flash the big orange "break" box like it does if you are about to hit something. There is no warning or sound. It just slows the car down for about 3 seconds and then resumes speeding back up. I'll have to mention it to the dealership and see if they can recalibrate something. In the meantime, thanks for the idea mrgold. I will see if I can just turn off ACC.

BLEXV6

Funny you should say this. I had my MDX go to regular CC, and could not figure how this happened. I thought something was wrong with the car. I did however find out that I must have disengaged it and somehow reengaged the ACC.