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In October 2016, my partner and I purchased a new BMWi3, without the range extender. We understand we were one of the first buyers of this updated i3 in the U.K.

Since then, in January 2017 (my partner driving) and again in April 2017 (when I was driving) we have had two accidents, both caused by a sudden unexpected, very powerful, acceleration surge.

We are interested to know whether any other i3 owners have experienced a similar event and what the outcomes were.
 

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Most likely explanation is either pressing the wrong pedal (heavy regen made you think your foot was on the brake, but it was actually on the accelerator) or you reengaged cruise control accidentally.
 

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In October 2016, my partner and I purchased a new BMWi3, without the range extender. We understand we were one of the first buyers of this updated i3 in the U.K.

Since then, in January 2017 (my partner driving) and again in April 2017 (when I was driving) we have had two accidents, both caused by a sudden unexpected, very powerful, acceleration surge.

We are interested to know whether any other i3 owners have experienced a similar event and what the outcomes were.
I have to ask; why didn't you do something about it after the first accident?
 

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I鈥檝e wondered about these occurrences. Certainly there is a history of pressing the wrong pedal in an automatic and going through the back of a garage etc.
However I wonder how fail-safe the accelerator pedal electronics are on these drive-by-wire cars these days.
I would hope there are at least two potentiometers and that the computer decides if one goes to 100% and the other one stays low then there鈥檚 a fault and it doesn鈥檛 go full pelt into the car in front.

If the system isn鈥檛 fail safe then there is going to be a growing amount of people who are falsely accused of not paying attention rather than a fault in the car being blamed.
How can you prove it was the car and not your foot that caused the acceleration, the answer is that you can鈥檛 unless you constantly record video of your feet and pedals.
 

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How can you prove it was the car and not your foot that caused the acceleration, the answer is that you can鈥檛 unless you constantly record video of your feet and pedals.
Tesla keeps a log of your actions including pedal presses
Don't know about the i3.
 

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The Safety Case for throttle by wire is huge. I'm not saying you can't have a fault, but the system is incredibly well prepared and you would struggle to evidence such an incident.
 

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I鈥檝e wondered about these occurrences. Certainly there is a history of pressing the wrong pedal in an automatic and going through the back of a garage etc.
However I wonder how fail-safe the accelerator pedal electronics are on these drive-by-wire cars these days.
I would hope there are at least two potentiometers and that the computer decides if one goes to 100% and the other one stays low then there鈥檚 a fault and it doesn鈥檛 go full pelt into the car in front.
The usual way drive by wire throttles are done (and naturally all EV's are drive by wire throttle!) is indeed to have two separate potentiometers on the same shaft, with two separate signals that are compared by the ECU to ensure coherence - if the estimated throttle positions indicated by the two signals is more than a small amount out a fault will be raised and the car will safely lose power.

But more than that, the ends of the potentiometer are wired opposite to each other, so that at closed throttle one is outputting near zero volts and the other near 5 volts, and at full throttle this is reversed. Only at half throttle would they output the same voltage.

This allows detection of a fault such as an open circuit in the signal or 5 volt supply wires - say the 5v supply went missing and both potentiometers then output 0v - this is an impossible situation outside of a fault because they should never both output 0 volts at any throttle position. Reversing the sense of the potentiometers in this way makes the coherence checking much safer and more robust, as there isn't really a fault scenario where the two reverse wired potentiometers could pass the coherence test.

While I don't think it's impossible to still have a "full throttle fault" in an EV or drive by wire system, it's actually much more likely to be a software bug/glitch than a faulty throttle pedal or cabling, if it happens at all.
 

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I actually think the fault is simultaneous pressing of the brake and throttle as in automatics, but with more throttle and not very much brake. Coding for the occurrence would be simpler and allow the user to disable the feature if they did not like it..
 

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I actually think the fault is simultaneous pressing of the brake and throttle as in automatics, but with more throttle and not very much brake. Coding for the occurrence would be simpler and allow the user to disable the feature if they did not like it..
Interesting thing is I notice on my Ion that if you press brake and throttle pedal at the same time it does still apply torque to the motor, however when the brake pedal is pushed more than a small amount the amount of torque available from the motor is severely limited even if the throttle is to the floor - you can see this by watching the eco-meter which shows the restricted power going to the motor.
 

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If the road gets a bit bumpy whilst using the regen brake, the regen can cut out quite abruptly. It can feel a bit like an acceleration, although all that is happening is the car has stopped braking.
It can feel a bit unnerving when it first happens
 

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yep when i put my ampera in "launch" mode i feel the torque application but even with my foot in the floor it wont move until i lft the break right off completly
 

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In October 2016, my partner and I purchased a new BMWi3, without the range extender. We understand we were one of the first buyers of this updated i3 in the U.K.

Since then, in January 2017 (my partner driving) and again in April 2017 (when I was driving) we have had two accidents, both caused by a sudden unexpected, very powerful, acceleration surge.

We are interested to know whether any other i3 owners have experienced a similar event and what the outcomes were.
I have just posted about a similar experience. Did you resolve the problem?
 

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If the road gets a bit bumpy whilst using the regen brake, the regen can cut out quite abruptly. It can feel a bit like an acceleration, although all that is happening is the car has stopped braking.
It can feel a bit unnerving when it first happens
I suspect that is what happened here - it can be very disconcerting.
 

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If the road gets a bit bumpy whilst using the regen brake, the regen can cut out quite abruptly. It can feel a bit like an acceleration, although all that is happening is the car has stopped braking.
It can feel a bit unnerving when it first happens
I suspect that is what happened here - it can be very disconcerting.
This potentially has implications for owners of the new Leaf 40 with e-pedal engaged I suspect.
 

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This potentially has implications for owners of the new Leaf 40 with e-pedal engaged I suspect.
I take it to brake you have to take your foot off the e-pedal, wonder how many people will press the e-pedal hard in an emergency situation.
 

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In October 2016, my partner and I purchased a new BMWi3, without the range extender. We understand we were one of the first buyers of this updated i3 in the U.K.

Since then, in January 2017 (my partner driving) and again in April 2017 (when I was driving) we have had two accidents, both caused by a sudden unexpected, very powerful, acceleration surge.

We are interested to know whether any other i3 owners have experienced a similar event and what the outcomes were.
Hello - I鈥檝e had my i3 for about 3 weeks and I had a terrible power surge and accident. I would love to discuss this with you. Would you and your partner like to discuss ? Melissa
 

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I have not experienced this in our new i3S but my wife reported something similar. Fortunately she was only doing a U turn at the time so a near miss rather than an accident. She took her foot off the accelerator expecting the car to slow down, and it surged forward instead. Because the turning circle is so small, the car cleared the obstacle in front, but it would have struck it otherwise.

Very interested to follow this thread and see if there is an underlying problem that BMW need to rectify.

We did not report our incident to BMW. Have any of you reported it?
 

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This seems to have occurred a few times, fortunately most owners have not experienced this, perhaps posting on the worldwide and UK i3 owners Facebook pages may yield more info.
 

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It is interesting how this keeps coming up. I have experienced the 鈥榮urge鈥 in both the Leaf and Prius. Completely different cars and makes. However the scenario is the same.
You are breaking gently on an approach to traffic lights or a junction. You hit a pot hole or manhole cover and the resulting bump makes the car 鈥榓ccelerate鈥 and you end up slamming on the brakes hoping you are not going to hit the car in front.
The main answers seems to be:
1) ABS has kicked in, ABS does not slow a car faster it just allows you to stay in control.
2) The hump causes the regen to stop leaving you with just the mechanical brakes. Which you now have to push harder to get the same effect.

Both the above effects cause the deceleration you were feeling (as you were slowing) to stop, which as you approach the car in front now feels like an acceleration.

The other completely different issue is unintended use of the accelerator than brake. This happens so often that car manufacturers record this (and win in court). Nissan now have a feature in the new Leaf that if you press the accelerator hard and it can see an object ahead it realises your mistake and activated the brake instead.
 
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