Thump! Complete Loss of Power on Freeway. Went into Neutral

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Not exactly the first post I was hoping for. I've lurked on this site a little bit in the past but today got to join this not-so-awesome club on my evening commute when I lost power. I was not able to make it across all 5 lanes of a busy freeway to the shoulder before coming to a complete stop halfway between two lanes (one of which was a busy merge lane from SFO airport). I tried to restart it (keyless) a couple of times without success- no messages on dash, rest of electronics (radio etc) still working fine. I did notice that the gauge dropped down to full "charging" as if the regen were fully engaged but not all the way to OFF which seemed odd. I hit the SOS button to ask them to send CHP since I was blocking traffic and genuinely feared for my safety. While on the phone with them some guys stopped and tried to push me to the shoulder since I was only 3/4 of a lane away but the car would not move at all. Shortly after they gave up, I randomly tried to start the car again and it did start. I was able to pull the shoulder and call off CHP. After collecting my nerves a bit I headed for the next off ramp and made it the rest of the way home on surface streets without incident. I will be taking the car to the dealer in the morning.

* What model year was your MB B EV? 2015

* Which mm/yy was it made (see label on driver door frame) 01/15

* When did you lease or buy your car, and how miles have you driven before this happened? Leased 05/14/15, has just over 2K miles

* Any error messages displayed on the instrument cluster when this happened? None.

* Do you recall if you were driving in D or D+ D- or D-auto when this happened? Not 100% sure but I think D-Auto. I usually drive in D- but I was talking to someone when I started my drive home and I don't think I ever put it in D-.

* Approximately where are you located? San Francisco Bay area

* Did you cancel your lease? or return the car if you bought it? Not yet? Will see what dealer says. I really love the car, but not if its going to try to kill me (or my family).
 
pharmama said:
Not exactly the first post I was hoping for. I've lurked on this site a little bit in the past but today got to join this not-so-awesome club on my evening commute when I lost power. I was not able to make it across all 5 lanes of a busy freeway to the shoulder before coming to a complete stop halfway between two lanes (one of which was a busy merge lane from SFO airport). I tried to restart it (keyless) a couple of times without success- no messages on dash, rest of electronics (radio etc) still working fine. I did notice that the gauge dropped down to full "charging" as if the regen were fully engaged but not all the way to OFF which seemed odd. I hit the SOS button to ask them to send CHP since I was blocking traffic and genuinely feared for my safety. While on the phone with them some guys stopped and tried to push me to the shoulder since I was only 3/4 of a lane away but the car would not move at all. Shortly after they gave up, I randomly tried to start the car again and it did start. I was able to pull the shoulder and call off CHP. After collecting my nerves a bit I headed for the next off ramp and made it the rest of the way home on surface streets without incident. I will be taking the car to the dealer in the morning.
Sorry this happened to you pharmama, I know how you feel. I have few more questions while the incident is still fresh in you mind...

Above you said you "lost power" while driving.
You also said the regen gauge dropped down to full charing.
You also said "no messages on dash".

Ok, here are my questions:

What speed where you driving when this happened?

What exactly what do you mean you "lost power"? What did you see on your dash when you lost power? Did you dash go 100% dark? Did any lights come on in the dash? Did all lights come on in your dash? Immediately after you lost drive, what did it show you were in: D, D-, D+, D-auto, N, P? (this important if you can remember)

During this whole incident, did you see any error messages? (just after you loss drive, during reboot, after reboot, rest of the day)

Please keep the forum posted as you work with Mercedes Benz. Thank you.
 
tom said:
Sorry this happened to you pharmama, I know how you feel. I have few more questions while the incident is still fresh in you mind...

Above you said you "lost power" while driving.
You also said the regen gauge dropped down to full charing.
You also said "no messages on dash".

Ok, here are my questions:

What speed where you driving when this happened?
Somewhere between 40-50mph in traffic

tom said:
What exactly what do you mean you "lost power"? What did you see on your dash when you lost power? Did you dash go 100% dark? Did any lights come on in the dash? Did all lights come on in your dash? Immediately after you lost drive, what did it show you were in: D, D-, D+, D-auto, N, P? (this important if you can remember)

Center screen in instrument/gauge cluster was totally dark and the car was not responding to input from the accelerator. It did feel a bit like the regen was engaged- that resistance to forward motion but that could also have been a fairly heavy car with no power. I was focused on getting out of traffic so I'm not 100% sure I could say for sure on all of these, unfortunately (and the screen was dark).

tom said:
During this whole incident, did you see any error messages? (just after you loss drive, during reboot, after reboot, rest of the day)

Nope. No messages at any point since the incident.
 
Doesn't sound like the infamous sudden jump to Neutral Tesla-drivetrain-speed-sensor Toyota recall problem. But I could be wrong of course. Please give us an update after diagnostic at MB. Thank you.
 
TomD said:
I just purchased a 2015 and it has under 500 miles. Today on freeway at 65mph the car suddenly switched to neutral and I had to pull over and initiate a restart - a bit unnerving and I was thankful it wasn't another member of the family or a busy time of day.

UPDATE: I brought the car into the dealership and they downloaded and re-installed the software. This was approximately 2 weeks ago. While the problem hasn't repeated itself, I believe what may have triggered the problem was playing around with the cruise control and collision prevention assist - to see how it works, etc. I haven't subjected the car to this kind of test since picking it back up from the dealer.
Thanks for the update TomD. Are you saying, going at 65mph, you might have put the car into Neutral? I haven't tried doing that while driving in "D", I am not sure the car will let us do that easily.

Did they find any fault codes? If so, it would be noted in your repair paperwork.
 
tom said:
Doesn't sound like the infamous sudden jump to Neutral Tesla-drivetrain-speed-sensor Toyota recall problem. But I could be wrong of course. Please give us an update after diagnostic at MB. Thank you.


yes, I agree that mine seems a little different but I did see at least one other one where the screen went dark. We'll see. Haven't heard back from dealer yet...
 
For those that have experienced this issue (and anyone else who wants to chime in), how big a deal is it? I am looking to buy or lease a B-class EV within the next few weeks, and reading about this is certainly giving me pause as it seems there is no evidence as of yet that MB is addressing it. I guess the short version is: would you feel comfortable that your wife and child are safe in the car knowing this issue is possible?
 
chrismc said:
For those that have experienced this issue (and anyone else who wants to chime in), how big a deal is it? I am looking to buy or lease a B-class EV within the next few weeks, and reading about this is certainly giving me pause as it seems there is no evidence as of yet that MB is addressing it. I guess the short version is: would you feel comfortable that your wife and child are safe in the car knowing this issue is possible?

In my case I am the wife but I did ask my husband how he would answer this question and it was similar to how I would. I'm torn. I absolutely LOVE the car. But my experience was very scary and in retrospect it would have been 10X worse with my kids in the car both in fearing for their safety and they would have been freaked out. I did feel obligated to share my experience (and this thread) with another B-Class owner I know as an FYI. I don't have my car back yet (see update below) but I am going to let them try to fix the issue. I have lost a bit of trust in the car though and that is unsettling.

As a minor update, my car has been at the dealer since Tuesday AM. They did find one fault code which it took them a bit and consultation with the MB "Mothership" to figure out. Update today is that MB has instructed them to replace the battery charging unit (I am unclear how this might be involved since battery charge wasn't a factor in my incident but didn't have a chance to discuss further with the service adviser yet). However, they won't even have an ETA on this part until hopefully tomorrow...
 
tom said:
chrismc said:
would you feel comfortable that your wife and child are safe in the car knowing this issue is possible?

Answer: N O !

Well I hate it just as much as the next guy, but it's not the end of the world. It's not the Prius ECU debacle, for instance. Looks like a reboot of the car fixes the problem (at least that was the case with my sudden loss of drive). My Electric Focus had numerous losses of power before they issued a recall, and that was worse - a reboot didn't fix it, at least not right away (you had to let the car sit for a while and reboot then). Now that was hilarious when the wife called me literally from the middle of a busy intersection.

Besides, a "normal" car can have an engine failure at the least convenient time, too, yet people keep driving gasoline cars. In most of those cases, a simple reboot in the middle of the intersection doesn't fix the problem.
 
phototrek said:
Well I hate it just as much as the next guy, but it's not the end of the world. It's not the Prius ECU debacle, for instance. Looks like a reboot of the car fixes the problem (at least that was the case with my sudden loss of drive). My Electric Focus had numerous losses of power before they issued a recall, and that was worse - a reboot didn't fix it, at least not right away (you had to let the car sit for a while and reboot then). Now that was hilarious when the wife called me literally from the middle of a busy intersection.

My B-Class did not 'reboot' immediately. I spent several minutes blocking 2 lanes of a busy freeway before it decided it would reboot.

phototrek said:
Besides, a "normal" car can have an engine failure at the least convenient time, too, yet people keep driving gasoline cars. In most of those cases, a simple reboot in the middle of the intersection doesn't fix the problem.

Sure. But a gasoline car that experiences engine failure within the first few months of ownership with multiple reports like this would cause plenty of alarm/concern as well.
 
pharmama said:
phototrek said:
Besides, a "normal" car can have an engine failure at the least convenient time, too, yet people keep driving gasoline cars. In most of those cases, a simple reboot in the middle of the intersection doesn't fix the problem.

Sure. But a gasoline car that experiences engine failure within the first few months of ownership with multiple reports like this would cause plenty of alarm/concern as well.

Let me tell you a story. Back in 2001, I took delivery of a beautiful new Audi S4. Blue with white leather interior, in many ways same as Beverly now (my wife says I'm predictable this way). The day my car was delivered I happened to be at the dealership, and I watched them unloading it from the truck. Two S4s were delivered that day: one fire red, and my beauty. Sadly, the red one didn't run - it made a terrible noise when cranked. Turns out that it had a bad valve that went thru the cylinder.

Five months later I heard this really awful sound...

2001-12-04-133205-b.jpg


Apparently there was a whole batch of engines with bad valves, and the two that were delivered that day had a valve just like that. 30 calendar days (and two new engines) later the car was lemoned, as required by CA law. This was my favorite Audi of all time (out of 6), but it didn't stop me from buying others afterwards. Shit happens.

RIP Pot.

pot.jpg
 
photo: can you briefly explain to us what exactly is California's lemon law? In lay person language, what has to happen before they will take back a car (or replace it)?
 
tom said:
photo: can you briefly explain to us what exactly is California's lemon law? In lay person language, what has to happen before they will take back a car (or replace it)?

Regardless in which state you bought / leased the car, the dealer had to provide a booklet of the lemon laws in all states along with other manuals etc., and by law they had to inform you of that booklet / show it to you. That booklet will tell you all that much better than I ever could :)

One aspect of the CA lemon law is that if the car can't be repaired within 30 contiguous calendar days, it triggers the lemon. My engine exploded and they couldn't get it back to work within 30 calendar dates (there was Xmas in between but that doesn't matter for the law). On the 30th day I was on the phone with Audi and once I told them that I am aware of the law and that I want to invoke the lemon, it all got resolved very quickly. They bought back the car, including loan interest, minus a $300 "Usage fee" - basically I rented the car from them for 5 months / 15k miles (yes I used to drive a lot) for $300, making it the best and cheapest rental in history.

In CA, it is at the manufacturer's call whether they will refund you the money and take the car back, or whether they will give you an equal car in its place. They pretty much always buy it out, as it creates less anger with the customer, if you want to have any chance whatsoever to keep them loyal.

There are other aspects of the law, such as how many times the car can break for the same reason, regardless how long it takes them to fix it, and so on. And of course each state is different.

Again, I recommend you read the booklet.
 
I experienced one of these episodes yesterday on my way to work. It was like the "gas" pedal just quit working. I still had power steering, the radio was still playing, etc. I was in D-Auto. No warning lights on the dash. Fortunately I was driving on a residential street. Were it not for lurking on this forum for the last two months I would have been much more scared by it. I coasted to the side of the road, put the car in park, and shut it off. When I turned the key to off, all of the warning icons on the dash came on. I waited less than a minute and started the car again, put it in gear, and it worked like nothing was wrong with it.
The dealer says bring it in.
(This is a 2014, I've had it almost 3 months. I've already had one software upgrade because I got the "take the car to the workshop" message the day after I brought it home.)
Is there any wisdom you can give me to avoid reinventing the wheel, so to speak?
Thank you.
 
NotYourMom said:
I experienced one of these episodes yesterday on my way to work. It was like the "gas" pedal just quit working. I still had power steering, the radio was still playing, etc. I was in D-Auto. No warning lights on the dash. Fortunately I was driving on a residential street. Were it not for lurking on this forum for the last two months I would have been much more scared by it. I coasted to the side of the road, put the car in park, and shut it off. When I turned the key to off, all of the warning icons on the dash came on. I waited less than a minute and started the car again, put it in gear, and it worked like nothing was wrong with it.
The dealer says bring it in.
(This is a 2014, I've had it almost 3 months. I've already had one software upgrade because I got the "take the car to the workshop" message the day after I brought it home.)
Is there any wisdom you can give me to avoid reinventing the wheel, so to speak?
Thank you.
Sorry you had this experience.

Can you describe the loss-of-drive incident in more detail for us?

You said you were driving in D-auto. Your foot pressed on the accelerator pedal and your car would not respond. So, was it still in D-auto? Or did you notice it went to "N"? (you said you still had power, such as power steering)

Anything else showing on the instrument display when this occurred? Any error messages before or after your reboot?

Hope you are not offended, but an important question: Is it possible you accidentally hit the gear select lever and put your car in "N"? (Note: the car, by design, will let you shift to "N" even when you are driving at high speed. So, while in DRIVE, if you hit that gear select lever up, the car will shift to "N")

Also, given that your is a 2014 (not keyless), is it possible you hit the key? (that could cause you to lose drive, but your A/C and radio would still be on)

In my case, my sudden loss-of-drive experience was very different than yours, my car simply stalled, as described here: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=359&p=2906#p2906

Other forum member's loss-of-drive incidents are listed here: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=380
 
There is not much more to describe. I was driving at about 15 mph (street with a lot of stop signs). Only a few blocks from my house. Both hands on the steering wheel, straight road. I don't think there is any possibility that I knocked either the gear shift or the key. I have been very alert to that given what I have read on this forum. I pressed the pedal to speed up and nothing happened. I tried again, no response, I tried again, realized I was nearly done coasting and pulled over. I looked at the dash and I was still in D-Auto. I did not notice what the battery charge indicator said.
In other people's incidents did the gear indicator actually say N? Mine was still in D-Auto. Nothing looked wrong on the dash. No warning symbols or messages until after I turned the car to off. Then all the icons lit up.
I did not have the A/C on. I had the windows open and the radio on.
What else do you want to know?
 
NotYourMom said:
There is not much more to describe. I was driving at about 15 mph (street with a lot of stop signs). Only a few blocks from my house. Both hands on the steering wheel, straight road. I don't think there is any possibility that I knocked either the gear shift or the key. I have been very alert to that given what I have read on this forum. I pressed the pedal to speed up and nothing happened. I tried again, no response, I tried again, realized I was nearly done coasting and pulled over. I looked at the dash and I was still in D-Auto. I did not notice what the battery charge indicator said.
In other people's incidents did the gear indicator actually say N? Mine was still in D-Auto. Nothing looked wrong on the dash. No warning symbols or messages until after I turned the car to off. Then all the icons lit up.
I did not have the A/C on. I had the windows open and the radio on.
What else do you want to know?
@NYM, Thank you for your detailed description of your loss-of-drive incident. I wanted to make sure there was no chance you hit the shift lever or the key accidentally. Given your response I added you to the LIST:

http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=380

Please keep us posted after your visit to your local MB service center.

p.s. As to what you can expect from MB, here is a heads-up for everyone with this kind of problem. I am still dealing with MBUSA in N.J. regarding my B stalling, I am having a terrible experience dealing with them. I am even in direct contact with the CEO of MBUSA by e-mail. They really don't seem to give a shit about our safety (in my case the car stalling while in drive). I am still talking to them, but it's not going well.
 
I experienced the sudden loss of power problem for the first time today.

Similar to others. Sudden loss of responsiveness from accelerator pedal. Car was NOT in neutral. It was in Drive. All other electronics seemed normal (dashboard and radio). Right side dial was pegged at 100% regen, though the car was not slowing as it would in full regen. I was in a very precarious position but managed to pull to the shoulder and come to a stop. I turned the car off and then on again, after which it seemed normal.

* What model year was your MB B EV? 2015

* Which mm/yy was it made (see label on driver door frame)
04/15

* When did you lease or buy your car, and how miles have you driven before this happened?
Leased 06/15/15, 2380 miles

* Any error messages displayed on the instrument cluster when this happened?
None.

* Do you recall if you were driving in D or D+ D- or D-auto when this happened?
D-Auto or D-.

* Approximately where are you located?
San Francisco Bay area, specifically San Jose on Northbound I-280. Very dangerous location as I had to cross several lanes of traffic and proceed about 1/2 mile before I could pull over.

* Did you cancel your lease? or return the car if you bought it? Not yet?
I'll schedule a service appointment and see what happens.

Follow-up:
I took my B-Class into Stevens Creek Mercedes Benz in Santa Clara to address the issue on 8/28.
They noted that there were many stored codes; PTCU U016883, U029283, U019B87 communication issue, Charger U19OBF1.
They noted that a software update was available and so they performed that.
My service adviser assured me that the software update will eliminate the sudden loss of power issue.
I've driven the car daily for the three weeks (600 miles) since service and have not experienced the problem so far.
 
NotYourMom said:
There is not much more to describe. I was driving at about 15 mph (street with a lot of stop signs). Only a few blocks from my house. Both hands on the steering wheel, straight road. I don't think there is any possibility that I knocked either the gear shift or the key. I have been very alert to that given what I have read on this forum. I pressed the pedal to speed up and nothing happened. I tried again, no response, I tried again, realized I was nearly done coasting and pulled over. I looked at the dash and I was still in D-Auto. I did not notice what the battery charge indicator said.
In other people's incidents did the gear indicator actually say N? Mine was still in D-Auto. Nothing looked wrong on the dash. No warning symbols or messages until after I turned the car to off. Then all the icons lit up.
I did not have the A/C on. I had the windows open and the radio on.
What else do you want to know?
The scary thing is that there was no apparent fault detected in the vehicle, which means nothing would be logged since the car doesn't believe there was any failure. With all of these reports of failures by owners it seems that it would be really nice to have the ability to record the state of the ECU and all sensors when the incident occurs, so that technicians could check it later. In computer parlance: essentially dump the current state of the ECU to non-volatile memory so that it can be retrieved later. To make it quick and easy for drivers a nice big LOG CAR STATUS on the dash would be helpful.

Of course that would imply that the manufacturer believes an error might occur car, which Tom's posting implies Mercedes apparently does not believe can happen.
 

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