I3 unsafe in winter weather?

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codingpanic

Member
Joined
Feb 9, 2016
Messages
8
BMW I3 is extremely dangerous in winter conditions. When Accelerating from a snow covered side street to a BUSY, clear, down to pavement main road, the car will suddenly stop for 3 seconds as if its thinking about what it is about to do. This is enough time that a car can rear-end you.

The inability to flat out disable regen braking in winter weather makes the car a challenge to drive. Who thought that automatic rear wheel braking only on snow packed roads is a good idea? Even when you try to moderate the brakes, the car slides. When you do get acceleration, the car will stop again, as if it is surprised it moved further. It stops, waits 3 seconds, then tries again.

Today, while driving on a road with a posted speed limit of 50, the I3 saw some snow fall from a tree in the distance. (not a lot of snow mind you, certainly not enough to warrant this reaction.) The car lurched to a stop without any driver input and I was nearly rear ended. I then angrily disabled the vehicle safety systems by pressing the car button on the dash.

This is not my first car, and I do, in fact know how to drive. I am afraid to drive in "tech" mode and disable all the electronic nannies so that I can have full control of the vehicle since BMW could potentially void the warranty. With stories of motor mounts breaking, something tells me that the car couldn't handle tires transitioning from snow packed road to a down to pavement main road.

The car is garaged, clean, and none of the driving sensors were obstructed in any way. This vehicle is clearly not the future. At least not in the winters of New England.

Please note that I am not driving on summer tires.
 
I have now driven my i3 on snowy roads quite a bit, in various conditions, and never experienced anything like what you describe....

And I'd add that the rear wheel drive gives quite amazing traction when the snow gets deep or wet...
 
codingpanic said:
What software version are you currently running? I'm running the latest November update...
Latest, as well.

Now maybe you ran into a specific bug that I never got to get to. I don't have any self driving options that could interfere (which is what your post kind of points too).
 
Yeah, I have Driver Assistant plus but I am not using adaptive cruise or any of those features. I am driving the car. The sudden braking only happened this morning though. I've been having acceleration issues whenever there are slick roads. Slow accel, brisk accel, nothing works. Put it into tech mode and I can drive anywhere I want...
 
Strange, I live in New England as well and have not experienced any of this. 8" of snow yesterday, 5+ a few days ago and the only snow problem I had was the giant plow-induced hump at the end of the driveway.
 
Are any of you using winter tires? I'm on all season tires right now. Still doesn't explain that the car is fine when in tech mode...
 
codingpanic said:
Are any of you using winter tires? I'm on all season tires right now. Still doesn't explain that the car is fine when in tech mode...

Nope. All-seasons.

And I have all of the driving assistant stuff. I am, however, trying to figure out whether I'm running the latest software. I may actually not be.

The only time the car has ever done the slamming on the brakes thing was in the 'sudden bright light versus tunnel' situation (not a snow situation).

Have you tried switching the Nanny warnings to 'Late'?
 
They are set to late right now.

At this point, my only recourse is to drive with it off. That will fix the sudden braking. Traction on the other hand, I need to find out what is going on there.
 
I've experienced a few bizarre things with ACC and the sensors. I have also had a couple of scary moments when I first drove the car in icy conditions, like the rear of the car kicking out because of the aggressive regen braking. Getting used to driving the car in these conditions takes some time but I agree that there should be a way to turn off regen braking in these conditions. The Volt can do it, why not BMW? I know others will post replies about how this is all controlled by the driver, but what happens in those "Oh shit!" moments when a foot reacts faster than the way it should react?

One day when it was snowy and icy out, the sensors in the front of the car weren't happy and the car was constantly thinking there was an obstruction. Still drove ok and didn't cause any sudden stops, which was good. Lately when I pull into my garage, the sensors don't seem to be active because the car doesn't warn me when I get to close to the back of the garage. I don't have anything manually turned off to prevent the sensors. When I get back in the car in the morning, the sensors are working fine and the car is blaring the warning sounds. Not comforting that these sensors appear to work when they want to.

I think overall the car has been great to drive in snowy conditions, even with the all season tires, but think it would be safer in icy conditions if there was a way to turn off regen braking, or at least make it less aggressive.
 
I also live in New England, but am a firm believer in the proper tires. IMHO, all-season tires are a joke for lazy people. If you want good performance from ANY car when it gets cold and the roads get nasty, invest in winter tires. The OEM Blizzaks are okay, the Nokian R2's are rated better. Either one will improve any vehicle's winter performance. I'm on my second winter with the car on the OEM winter wheels/tires, and I have not experienced the problems listed except for the warnings, which can be a result of partially blocked sensors, and in this time of the year, more likely the camera sensor high up on the windshield. Keep that area clean, along with those on the bumpers. There are pros and cons to using a camera and ultrasonic verses radar...the radar would tend to use more power, but the camera can recognize things like pedestrians or wild animals that might be about to cross your path. I will say that getting started on slippery surfaces can cause the car to seem like it is barely moving...it really does try to minimize wheel spin and will limit the power available. If the roads are really nasty, use one of the Eco modes, or be very careful. FWIW, rear-wheel drive vehicles have this issue. A high performance ICE with a manual transmission can have exactly the same issue as regen braking on the EV...the rear end breaking loose, but in that case, from engine braking verses intentional regen (which you can control, while you can't anywhere as easily on an ICE). Modern automatic transmissions on ICE vehicles, not so much of a problem, as they tend to go into coast mode for maximum fuel economy when you let off unless you are manually in a lower gear.
 
brorob said:
I have also had a couple of scary moments when I first drove the car in icy conditions, like the rear of the car kicking out because of the aggressive regen braking. Getting used to driving the car in these conditions takes some time but I agree that there should be a way to turn off regen braking in these conditions. The Volt can do it, why not BMW? I know others will post replies about how this is all controlled by the driver, but what happens in those "Oh shit!" moments when a foot reacts faster than the way it should react?
The November update delays the strong application of regen for a second or two after the accelerator pedal is lifted completely, so sudden loss of rear wheel traction due to strong regen shouldn't be as bad as with earlier software versions.

brorob said:
One day when it was snowy and icy out, the sensors in the front of the car weren't happy and the car was constantly thinking there was an obstruction. Still drove ok and didn't cause any sudden stops, which was good.
I'm pretty certain that the camera in the rear view mirror housing, not the ultrasonic sensors in the front bumper, is responsible for activating the brakes when an obstruction is detected and the driver is doing nothing to avoid the obstruction. So ultrasonic sensors covered by snow or ice and therefore not functioning shouldn't cause any driving problems. They could cause the obstruction warning to sound inappropriately, but this warning can be turned off when this happens.

borrow said:
I think overall the car has been great to drive in snowy conditions, even with the all season tires, but think it would be safer in icy conditions if there was a way to turn off regen braking, or at least make it less aggressive.
To turn off regen braking, just shift into N. The November update makes the initial regen less aggressive. So all your problems are solved :)
 
jadnashuanh said:
FWIW, rear-wheel drive vehicles have this issue. A high performance ICE with a manual transmission can have exactly the same issue as regen braking on the EV...the rear end breaking loose, but in that case, from engine braking verses intentional regen (which you can control, while you can't anywhere as easily on an ICE).
I would much rather have the rear end than the front end break loose during engine braking or regen. In a FWD car, when the front end breaks loose, steering and front wheel braking are lost, so the car is essentially out of control. In a RWD car, when the rear end breaks loose, steering and front wheel braking are still available to control the vehicle.

I drove RWD rear- and mid-engine vehicles in Vail, CO, for a decade. I much prefer them to a FWD vehicle because I feel that a RWD vehicle with a considerable amount of weight over the rear wheels is more controllable, especially if one has a manual hand brake that will apply only the rear brakes when front wheel traction is lost during hydraulic braking. If the i3 had a manual hand brake, I think it would be a great slick road vehicle.
 
I just read the manual. It says that braking intervention is active up to 35 mph in the Intelligent Safety systems, but some of these passages are very confusing.

It says that the equipment varies by country (okay) so I got out my window sticker to see what is listed. For instance, in the manual it says that a picture of a person will light up as part of the pedestrian detection and that there is braking intervention.
There is a separate paragraph about braking intervention being active for this and the collision warning and it says that it is active "even when the adaptive cruise control is off". We do know that the car does brake above 35 when ACC is on.
However I have never felt or seen it do so outside of that - even when the little car icon lights up and/or beeps. Furthermore, I don't see a person icon anywhere in the display. Just a little car. Pedestrian detection does not appear in the list of things that come with the ACC/safety package...

I realize these systems are not substitutes for driving properly, but still. In reference to the poster describing the situation they encountered, it might also be helpful to have a little more information about what we can expect (or not) from these systems. I've never had them in a car before.
 
jadnashuanh said:
I also live in New England, but am a firm believer in the proper tires. IMHO, all-season tires are a joke for lazy people. If you want good performance from ANY car when it gets cold and the roads get nasty, invest in winter tires.
....., and I have not experienced the problems listed except for the warnings, which can be a result of partially blocked sensors, and in this time of the year, more likely the camera sensor high up on the windshield. Keep that area clean, along with those on the bumpers.
alohart said:
I'm pretty certain that the camera in the rear view mirror housing, not the ultrasonic sensors in the front bumper, is responsible for activating the brakes when an obstruction is detected and the driver is doing nothing to avoid the obstruction. So ultrasonic sensors covered by snow or ice and therefore not functioning shouldn't cause any driving problems. They could cause the obstruction warning to sound inappropriately, but this warning can be turned off when this happens.
I agree and I have been running winter tires on my vehicles for as long as I can remember, but the i3 was a splurge for me and I couldn't afford a set of winter wheels but am hoping to next year. So thanks for the lazy person comment..

I thought the proximity sensors in the bumpers controlled the warning sounds and visuals on the display, not the camera. This would seem to make more sense with the separate zones that are displayed on the screen (front and rear) when close to an object. I'll definitely check the windshield if this happens again.

alohart said:
The November update delays the strong application of regen for a second or two after the accelerator pedal is lifted completely, so sudden loss of rear wheel traction due to strong regen shouldn't be as bad as with earlier software versions.
I've been meaning to take the car in for this update. I've read a few posts from you and other members about the software update observations. Also been trying to keep track of any glitches I run into to see if the update solves these.

alohart said:
To turn off regen braking, just shift into N. The November update makes the initial regen less aggressive. So all your problems are solved :)
I'm a bit nervous of putting the car in N while driving. Is there a safety mechanism that prevents an accidental shift into R?
I agree with your comment about the stronger regen on the rear wheels is safer than the fronts. Still was I bit tricky to get used to on icy roads.
 
brorob said:
I thought the proximity sensors in the bumpers controlled the warning sounds and visuals on the display, not the camera. This would seem to make more sense with the separate zones that are displayed on the screen (front and rear) when close to an object. I'll definitely check the windshield if this happens again.
They definitely do sound warnings and display visuals when a very close obstruction is detected, but they don't have the range to detect an obstruction in the distance while driving; that's the camera's responsibility. It might be that the ultrasonic sensors are active only at low speeds, but I don't know that for a fact. I just know that while driving, I've never heard or seen the warnings that the ultrasonic sensors trigger when maneuvering at low speeds.

brorob said:
I'm a bit nervous of putting the car in N while driving. Is there a safety mechanism that prevents an accidental shift into R?
Yes. Some i3 owners braver than me have tested this behavior.

I don't normally shift into N while driving. However, I have twice avoided accidents on icy roads by disengaging the clutch of a manual transmission or shifting an automatic transmission to neutral when the rear wheels lost traction due to engine braking. But with today's advanced traction control systems, this probably isn't as problematic as in the old days.
 
I'm just about through my second winter with my i3 using Blizzaks. The car has been exceptional in the snow and ice, much better than what I'd consider average. If you're having difficulty as described, you should definitely have the car checked out.
 
Second winter for me with the i3. First year with Nokian R2's. Infinitely better than the Blizzak (yes I tried them on my neighbor's car who also has an i3). The nanny interventions that are being described are not normal based on my experience with the i3. I have driven the car in over 14 inches of snow that was not plowed and the it was astounding how good it was. I have sold my MB Gwagen because I just don't need it anymore as I was saving it for some really bad days. The combination of really skinny little gumballs located below the major weight in the car (gas and electric motor/engine) and reasonable ground clearance make this my new bad weather car of choice. I like it better than my wife's new Golf R with all wheel drive and studded Hakka's. Something is definitely not right, have it checked.
 
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