wedona
Posts: 4
Joined: Wed Jul 07, 2021 6:21 pm

What model year did adaptive cruise control get better?

Wed Jul 07, 2021 6:27 pm

Trying to decide which model year to get, and looking for input on this.

This owner comments on the adaptive cruise control improving significantly from 2017 to 2021:
https://www.reddit.com/r/BMWi3/comments ... _21_bev_s/

Did this happen with the 2018 mid cycle refresh/LCI?

Or with 2019 and the introduction of the largest battery size?

Or, as IIHS shows the front crash prevention rating applying separately to 2017-2019, and 2020-2021, was the ACC improved with 2020? Both test results show 9 and 7 mph reductions, so perhaps this was just to denote a change in optional versus standard equipment?
https://www.iihs.org/ratings/vehicle/BM ... to-vehicle
https://www.iihs.org/ratings/vehicle/BM ... to-vehicle

It seems least likely that this is a 2021 improvement given the end of production, but this could be a possibility too?

alohart
Posts: 2432
Joined: Sat Nov 01, 2014 7:36 pm
Location: Honolulu, HI

Re: What model year did adaptive cruise control get better?

Wed Jul 07, 2021 9:20 pm

The i3's ACC camera has 4 different parts numbers with the current version being installed since November, 2018, although the previous version was apparently installed through May, 2019. I don't know whether the low-resolution (VGA) grayscale camera or ACC's software was improved over the years. The Reddit poster didn't address the biggest problem with the i3's ACC which is that it can suddenly turn off when blinded by the sun, by heavy rain or fog, or by entering a dark roadway under a bright area above the roadway.

The behavior of ACC in stop-and-go traffic seems to depend on driving mode in our 2014 BEV. I almost always drive in Eco Pro with ACC on and have noticed that acceleration seems to be slower when a vehicle ahead begins moving than it is when in Comfort mode. ACC begins decelerating later than I would in many situations resulting in more aggressive deceleration than I prefer, so I frequently disable ACC when I see traffic slowing or stopping ahead.

The IIHS report, purportedly for the 2020 i3, indicates that the model tested was a 2017 i3 :!: Maybe the IIHS knew that the safety equipment and basic design had not changed, so they just used the 2017 test data for the 2020 model.

My own opinion is that neither ACC nor the safety equipment has improved much if at all over the years. If I were to replace our 2014 BEV, it would be with a 2018 or later BEV, mainly because of their larger capacity battery packs but also because of some of the LCI changes.
Aloha,
Art

2014 BMW i3 Arravani Grey, Giga World, Tech + Driving Assist, Parking Assist, DC Fast Charging, JuiceBox EVSE

gt1
Posts: 386
Joined: Sat Nov 07, 2015 7:31 pm
Location: Baltimore

Re: What model year did adaptive cruise control get better?

Fri Jul 09, 2021 8:00 am

I have a late build 2018, and ACC feels a bit better than the one in 2015 I had before. It is less prone to bailing out in the slightest weather changes.
My other car is Chrysler Pacifica with Bosch radar based ACC, and it can run circles around i3.

wedona
Posts: 4
Joined: Wed Jul 07, 2021 6:21 pm

Re: What model year did adaptive cruise control get better?

Sun Jul 11, 2021 6:12 pm

I test drove a 2018 model, at 3 or 4 following distance, following cars at 45mph to 0 at a stoplight, and while the car started slowing, it seemed to react really late. Not sure I'd trust it or if it's really usable.

I can only hope this is the performance of the "old" 2017 system? I may try a 2019 model next.

I'm curious, if any of you could comment on the forward collision warning? Even on older models, does it ever alert you soon enough to be useful? I'm now considering the 5AT package just for this feature as the ACC doesn't seem too usable.

alohart
Posts: 2432
Joined: Sat Nov 01, 2014 7:36 pm
Location: Honolulu, HI

Re: What model year did adaptive cruise control get better?

Sun Jul 11, 2021 8:54 pm

wedona wrote:
Sun Jul 11, 2021 6:12 pm
I test drove a 2018 model, at 3 or 4 following distance, following cars at 45mph to 0 at a stoplight, and while the car started slowing, it seemed to react really late. Not sure I'd trust it or if it's really usable.
That seems like the behavior of ACC in our 2014 i3. However, I always have ACC on when I drive in mostly suburban and urban driving conditions. If I don't want to wait for ACC to pull away from a stop, I just poke the power pedal which "awakens" ACC to start accelerating. If I see traffic decelerating way ahead, before ACC's low-resolution camera detects the slowing traffic, I pause ACC to allow me to control deceleration. I consider ACC to be an additional eye on traffic that might detect something that I miss which could avoid an accident. I wouldn't buy an i3 without it.

If you expect ACC to be a basic self-driving system rather than a driving aid, you might be disappointed.
wedona wrote:
Sun Jul 11, 2021 6:12 pm
I'm curious, if any of you could comment on the forward collision warning? Even on older models, does it ever alert you soon enough to be useful? I'm now considering the 5AT package just for this feature as the ACC doesn't seem too usable.
The forward collision system works only below 35 mph. IIHS safety tests indicate that the automated forward collision system doesn't prevent collisions above even the slowest speed they tested, 12 mph, at which speed the system reduced the collision speed to 3 mph. Before the automated system begins hard braking, a loud audible warning sounds alerting the driver to begin braking. I've experienced the loud warning and hard braking twice. This occurred when I was traveling at less than 5 mph and prevented collisions in both cases although I was aware of what I was doing and would not have collided. At least I know that the system works to at least reduce the severity of collisions. I've never experienced a false alarm.
Aloha,
Art

2014 BMW i3 Arravani Grey, Giga World, Tech + Driving Assist, Parking Assist, DC Fast Charging, JuiceBox EVSE

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