[Random]

2017 Gen 2, Doing about 58 on a local divided four lane highway, ACC on, L. Approaching an overpass, with dark concrete pillars in the center between the two directions, the car saw something and flashed the red collision lights and slowed somewhat aggressively for about 1 second, then recovered on its own. Because I was in L, no idea if the deceleration was EM alone or if brakes were actually applied.

By the time I decided there was no actual danger (I think literally between one and two seconds), it resumed before I could push on the accelerator pedal.

No actual danger or harm, however had someone been on my tail, it might have been somewhere between annoying to bad.

No idea if it saw and misinterpreted the pillars, or something on the road? approaching sunset, but it was still bright out.

 

[Tomt]

I've had similar incidents on rare occasions... I just rack it up as a temporary data error...

 

[Kraven]

Had the same exact thing happen in similar circumstances recently, http://gm-volt.com/forum/showthread.php?270281-Light-Conditions-Time-of-Day-and-their-impact-on-ACC

 

[edk-austin]

Interesting that the ACC computer feels it's still in control, as it's not dropping out of ACC.
My 2014 once dropped out of CC, beeping FCA, as I passed a tractor trailer on a gentle right curve at highway speed. I think I did have traffic behind me that time too.

 

[16513]

Normal behavior. Happens in tight left turns with parked cars, too.

 

[Random]

Dashcam to record FCA false alarm (if repeatable?)

Ordered an A119 dashcam from spytec, it will be interesting to see if some of the highway false alarms are repeatable and can be documented, or if it is just some weird combination of weather (snow/ice), sun angle, etc.

spent way too much time trying to decide which dashcam to buy, some good information here: https://dashcamtalk.com

This is the one I decided to try: A119 1440p Car Dash Camera with GPS Logger

 

[2VoltFamily]

I have had many false positive alerts on my 2013s. Most of the time it had to do with shadows or rounding a curve.

 

[Random]

I have had many false positive alerts on my 2013s. Most of the time it had to do with shadows or rounding a curve.

The difference is that 2017 ACC/FCA/FAB (Forward Automatic Braking, FCA is just the alert) can apply the brakes. So far, not an issue, but it could make false alarms more interesting (or, perhaps just a occasional minor nuisance). You can drive through the active braking too, so the driver remains in control, which is good.

Also, reviewing the manual (page 210), FAB is only active between 5 mph and 38 mph, so likely was not involved at 58 mph. I guess the deceleration I felt was ACC alone reacting to the FCA, what ever it was doing for that split second.