Reboot whilst driving, stiff brake pedal and loss of regen

[jamie94bc]

I've had my i3 for slightly over 2 months (1.2k miles) now, I've noticed a few little niggles that have been mentioned on the forum (such as the loud clonk) and also these...

Reboot Whilst Driving
Luckily this has only ever happened to me once. Everything rebooted with the exception of the speedo (and the car still drove okay). The warning / standard car lights around the speedo display came on, it made the startup chime noise, everything. A pretty scary experience when you're driving on twisty B roads at 50mph!

Stiff Brake Pedal
I've noticed occasionally the brake pedal gets really hard to push on - sort of like during hill hold. It's actually pretty dangerous because you really have to push hard to get it to brake - something which is thankfully unusual with the regen.

Loss of Regen
This is a strange one. I can't decide whether it's deliberate, a flaw or just being a little bit over zealous. The car seems to suddenly lose it's regen heavy cornering, or roundabouts, which is mostly fine - I presume this is due to the differential (if it has one) / traction control. The problem is that sometimes it randomly stops regen, even in a straight line or a slight bend, it also occasionally won't restart regen after a corner. At this point it just feels like the car is running away on it's own.

Anyone else experienced the same sort of problems?

 

[AndyW]

Hi Jamie

Not the first two, but definitely the last one! I put it down to the car not wanting to be unsettled by braking too much while cornering, possibly leading to lift-off oversteer. Doesn't seem likely (!), but that was my explanation.

 

[jamie94bc]

Hi Jamie

Not the first two, but definitely the last one! I put it down to the car not wanting to be unsettled by braking too much while cornering, possibly leading to lift-off oversteer. Doesn't seem likely (!), but that was my explanation.

Yeah that definitely sounds feasible, hopefully it's something they will be able to improve in the future - I'm guessing they're collecting a decent amount of telemetry.

Are the software updates OTA or do you have to go to a garage, how do you know if there is one available?

 

[seb]

Are the software updates OTA or do you have to go to a garage, how do you know if there is one available?

You have to go to a garage for driving, media and telephone software updates.
There is one update waiting for you if your media version is <= MN-002.031.006.

 

[Gonville]

I thought the update can be done on that via a USB? Using the software update option in the menu?

 

[Surge]

Could the loss of regen be due to the battery being full?

 

[Gonville]

Could the loss of regen be due to the battery being full?

I think this is the stability control that reduces regen when cornering so as not to impact steering under braking?

 

[jelloslug]

Loss of Regen
This is a strange one. I can't decide whether it's deliberate, a flaw or just being a little bit over zealous. The car seems to suddenly lose it's regen heavy cornering, or roundabouts, which is mostly fine - I presume this is due to the differential (if it has one) / traction control. The problem is that sometimes it randomly stops regen, even in a straight line or a slight bend, it also occasionally won't restart regen after a corner. At this point it just feels like the car is running away on it's own.

Anyone else experienced the same sort of problems?

I noticed the change in regen when test driving a production US model. I was coming off an expressway at around 60 MPH and rounding the cloverleaf to the surface road in an "energetic" manor. As I rounded the curve there was a distinct change in regen and I attributed it to the stability control as it "felt right".

 

[Gonville]

There's a whole other thread on this loss of regen thing from a qualified source.

http://www.mybmwi3.com/forum/viewtopic.php?f=11&t=986&hilit=Understeer

I have a long and bumpy/twisty stretch of road near me which goes quite steeply downhill (or uphill depending which way I'm going!)

I'm also a former racing driver...!

Going downhill in my i3 BEV I can feel the regen increasing/decreasing as it goes over bumps, which I'm sure is to prevent possible rear wheel locking. I haven't noticed any instability when going fast into corners, in fact it's a great point and squirt machine on a twisty road with tremendous acceleration out of corners. You're right that the regen is reduced when the front wheels are turned - any race car with too much rear brake bias is very unstable in corners. I also suspect, but don't know for sure, that pressing the brake pedal also stops regeneration so as to provide proper balance front to rear. The brakes are very good.

One thing I have noticed is a tendency for the front wheels to get pulled into a turn if you hit a cats eye or bump side-on - that can be quite scary given how direct the steering is!

There's certainly a lot of complicated calculations being done at high speed - pretty impressive!