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

B-Class Electric Drive Forum

Help Support B-Class Electric Drive Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I had a second bizarre thing happen with the car this weekend. I was driving along and I got a message on the dash to check the right rear brake light and check the right rear turn signal (I have about 1500 miles on the car). The two messages alternated on my dashboard until I got to my destination. I asked my passenger to get out and see if the right rear brake light and turn signal were working. They were not. I shut off the car for a few hours. When I started up again, I was still getting the same messages. We made one more stop on the way home, still got the messages. Then on the next leg of the trip, the messages went away, and it also seemed that the turn signal was working. We checked the lights on arrival at home and both the brake light and the right turn signal were working.

During the time when they were not working, the flash rate of the right turn signal on the dash was higher than normal.

I have an appointment with the dealer tomorrow to see if they find anything wrong with the car. It seems to have a mind of its own. I'll let y'all know what the dealer says.
 
SuperB said:
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.
I added you to this list: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=380

Please keep us posted after you visit your local MB service center.
 
I have my car back from the dealer. This is what they did:

Under labor, it says Update Powertrain Modeule, Update Powertrain Gateway Module, Update Air Conditioning Module.
Under parts, it says .1540 Recall. Flash, PTCU, Power Train Gateway and A/C Control Units as per campaign 201507002.

The guy in the service department says that the July software update is supposed to address the "acts like it's in neutral" problem.

(And as for my brake light / turn signal problem, they replaced a defective bulb.)

I don't know whether this is consistent with what other owners are being told, and of course it is too soon to know if any of this fixes the problem.
 
NotYourMom said:
I have my car back from the dealer. This is what they did:

Under labor, it says Update Powertrain Modeule, Update Powertrain Gateway Module, Update Air Conditioning Module.
Under parts, it says .1540 Recall. Flash, PTCU, Power Train Gateway and A/C Control Units as per campaign 201507002.

The guy in the service department says that the July software update is supposed to address the "acts like it's in neutral" problem.

(And as for my brake light / turn signal problem, they replaced a defective bulb.)

I don't know whether this is consistent with what other owners are being told, and of course it is too soon to know if any of this fixes the problem.
Thank you for updating us @NYM. So looks like they did some firmware update. Did they swap out any any hardware items?

On your service receipt, did they list all the fault codes they found? If so, would appreciate it if you could also list them here.

On my service receipt the fault codes were: U016883, U029287, U021283; but my local service tech said those three codes didn't tell them why my car stalled. I am still working with MBUSA to identify why my car stalled. We now think there is a known stalling bug for the 2015 B and Tesla gave them a fix (firmware). We are trying to find out if they roll out the fix yet, if so when, and if it's on my car. MBUSA is a big organization they don't move quickly.
 
The receipt says "no codes."
I'm not sure if they replaced any parts. To me it looks like it was all a software update.
 
Today, my B-Class Electric had a sudden loss of power. Here's the details:

Left the house in San Diego at 7:00 am.
Outside temperature about 75+degrees.

About 1 mile from the start, I braked slightly to maintain speed of about 25 MPH, coasted towards and uphill, put my foot on the accelerator to maintain speed and there was no power-just coasting. There was no unusual sound and no warning displayed. The car appeared normal except the guage was showing full regenerative braking while the car was coasting. Transmission was in D-auto. Power steering worked, AC and radio were still on. I brought it to a stop. Pushed the button to turn it off. At that time all the lights on the dash lit up. I pushed it again and the car was back to normal with the indicator showing zero between regeneration and discharge. I finished the drive without further incident.

Mileage: 1620 miles
Purchased: June 2015
Mfg date: 4/15

Took the car to the dealer two hours later and told them about the problem and that the forum says there is a code update available. Waited there for 3 hours. Their paper work says:
1639 541011, 540991, 540992. PROGRAMMED POWER TRAIN CONTROL UNIT. PERFORMED SHORT TEST; NO RELEVANT FAULT CODES. CHECKED POWER TRAIN CONTROL UNIT FOR SOFTWARE UPDATES. UPDATE WAS AVAILABLE. PROGRAMMED AND CODED POWER TRAIN CONTROL UNIT. COMPLETE.
When I retrieved the car, the mpkwhr was registering 12.4 (it read 2.7 when I brought it in), the miles left gauge read about 85 at 3/4 charge and, the overcharge button indicator was lit. I was able to reset everything back to normal.

Coincidentally there was another B-class pulling into the dealer at the same time. His was built in November'14. He said his dash indicator said to bring the car to the dealer. He had no other symptoms. I told him my problem and about the code update.

As a side note, my only other complaint on the car is that the collision warning sound comes on from time to time for no reason. The dealer says that can happen.

I'm assuming the code upgrade will fix that sudden power loss problem. Let me know if I missed anything in the description.
 
Jeff said:
Today, my B-Class Electric had a sudden loss of power. Here's the details:

Left the house in San Diego at 7:00 am.
Outside temperature about 75+degrees.

About 1 mile from the start, I braked slightly to maintain speed of about 25 MPH, coasted towards and uphill, put my foot on the accelerator to maintain speed and there was no power-just coasting. There was no unusual sound and no warning displayed. The car appeared normal except the guage was showing full regenerative braking while the car was coasting. Transmission was in D+. Power steering worked, AC and radio were still on. I brought it to a stop. Pushed the button to turn it off. At that time all the lights on the dash lit up. I pushed it again and the car was back to normal with the indicator showing zero between regeneration and discharge. I finished the drive without further incident.

Mileage: 1620 miles
Purchased: June 2015
Mfg date: 4/15

Took the car to the dealer two hours later and told them about the problem and that the forum says there is a code update available. Waited there for 3 hours. Their paper work says:
1639 541011, 540991, 540992. PROGRAMMED POWER TRAIN CONTROL UNIT. PERFORMED SHORT TEST; NO RELEVANT FAULT CODES. CHECKED POWER TRAIN CONTROL UNIT FOR SOFTWARE UPDATES. UPDATE WAS AVAILABLE. PROGRAMMED AND CODED POWER TRAIN CONTROL UNIT. COMPLETE.
When I retrieved the car, the mpkwhr was registering 12.4 (it read 2.7 when I brought it in), the miles left gauge read about 85 at 3/4 charge and, the overcharge button indicator was lit. I was able to reset everything back to normal.

Coincidentally there was another B-class pulling into the dealer at the same time. His was built in November'14. He said his dash indicator said to bring the car to the dealer. He had no other symptoms. I told him my problem and about the code update.

As a side note, my only other complaint on the car is that the collision warning sound comes on from time to time for no reason. The dealer says that can happen.

I'm assuming the code upgrade will fix that sudden power loss problem. Let me know if I missed anything in the description.
Sorry this happened to you Jeff. Thank you for the detailed description above, your sudden loss of drive incident sounds a lot like a few others that were reported here.

(Note: this web site will let you edit your old posts, there is an edit button at bottom right corner of your old post. So please feel free to go back and fix that D+ / D-auto thing in your original post.)

I have added you to the loss-of-drive list:
http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=380

Please give this forum an update if anything bad happens again.
 
Seems like there have now been at least 2 other incidents similar to mine (shows full regen) in addition to the jumping to neutral incidents.

Also interesting about one aspect of the CA Lemon Law being 30 days... my B is still at the dealer. Will be 28 days on Monday.

They told me there was a fault code (I don't know which one since I don't have service paperwork yet) which they had to consult with MB on how to address. MB told them one of the control units needed to be replaced. Took several days to get the part which apparently came directly from Tesla (which is right across the bay from us but whatever. Maybe it had to go through some bizarre Tesla-MB procurement chain). They installed the part but were waiting for confirmation from MB that they had the appropriate software versions for the new part. Days go by with them trying to verify this before they find out the person they had been working with at MB was now out of the office. At this point, they go further up the 'food chain' and consult with Germany. Germany instructs them to put in a different control unit (well, the same part but a different physical one) which they are shipping from Germany. The German part hasn't arrived yet...

Will update further when I know more.
 
Thank you for that update pharmama. After you get your car back please ask them exactly what was the fault that caused your sudden loss-of-drive, which parts they changed, which firmware was updated to which control unit, this way the rest of us here on this forum will be more informed of these sudden loss-of-drive issues.

For me, it's been 5 weeks since I first contacted MBUSA about my stall problem. My 2015 B stalled on me on the third day of my three year lease. My local MB service center was not able to identify the cause of the stall, so I contacted MBUSA for help.

The first guy (with initials JH) MBUSA assigned to my case wasted 3.5 weeks and didn't do anything. I knew he was bad news because when he first contacted me he immediately started to talk about the Lemon Law. After 3.5 weeks of jerking around he concluded I should use the Lemon Law to deal with my stall problem. He did zero technical investigation regarding the stall problem, except to verify I was at my local MB dealership. Frustrated, I e-mailed directly to the CEO of MBUSA about this ridiculous response. The CEO had this guy's boss take over my case (11 days ago), and the new lady is much better, a much better listener and logical thinker.

Learning through more than one channel, we now suspect there is at least one known bug that can cause the 2015 B to stall, and that Tesla already has a fix for it. It is not clear if Tesla has given this fix to MB, or if MB has rolled out the fix yet. That's the info I have as of today. The customer support lady taking care of my case is trying to: 1) verify this known fault that can cause the 2015 B ED to stall, 2) verify there was a fix from Tesla, 3) verify MBUSA has rolled out the fix, 4) make sure the fix is in my car. I suspect this is a firmware fix, but I can't be sure until she verifies this with the engineers at MBUSA and/or Germany.

(Note: My 2015 B simply stalled while in "D", it did not suddenly jump to neutral. The sudden jump-to-neutral problem is probably caused by a different fault, possibly similar to the Toyota RAV4 EV recall)

I showed MBUSA this forum and this list:

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

and informed them we had three new cases of sudden loss-of-drive last week. I suspect only 20% to 25% of the people driving this car are members here on this forum.
 
Leased my B class on June 23, 2015. Today the car lost power twice which brings my total to 5 times since I leased it.

This is extremely dangerous.

I brought the car in 2 weeks after leasing it as an error message came on after charging it at the Merecedes dealership. After 5 days of driving a loaner gas car, they did nothing and told me the error message came on due to a problem with their charger. That's after they communicated with Tesla, New Jersey and Germany. So I'm not oozing with confidence that they know how to handle these cars. If anyone can confirm that a firmware update will resolve this issue, I'll take it back in.

Thanks.

Chris
 
Chris,
I think it would be worthwhile to get the firmware update. I have not had another problem with mine since they did the update. (Of course, you never know you are going to have the problem until you have it, so it could happen again tomorrow. All I can say is it hasn't happened again yet.) Perhaps others who have gotten the firmware update can also report on whether they had any other incidents after the update.
 
I've traveled 735 miles since my firmware reflash and have not had any power loss incidents nor any other issues. Since the original problem didn't show up for over 1600 miles, I don't think I've proven that the firmware upgrade will fix the problem but it is a good sign. I'll post another update when I get more miles on the car.

These comments probably belong in another thread:
Aside from that, my wife and I are extremely happy with this car. Yesterday, I knew I would be driving a lot and used the overcharge button which added quite a few miles to the range. It appears that once you drive off those extra miles, the range gauge needle starts indicating the same relative drops as without the overcharge. For me, that's about 5 miles per tick mark (conservatively). I don't find the numeric miles left indicator to be too useful since it is way too conservative.

I also wanted to note that we have a 40 amp, 220v charger. If you buy a home charger, get the bigger one. Most are 30 amp which will not take advantage of the cars full charging capability.
 
CM23 said:
Leased my B class on June 23, 2015. Today the car lost power twice which brings my total to 5 times since I leased it.

This is extremely dangerous.

I brought the car in 2 weeks after leasing it as an error message came on after charging it at the Merecedes dealership. After 5 days of driving a loaner gas car, they did nothing and told me the error message came on due to a problem with their charger. That's after they communicated with Tesla, New Jersey and Germany. So I'm not oozing with confidence that they know how to handle these cars. If anyone can confirm that a firmware update will resolve this issue, I'll take it back in.

Thanks.

Chris
CM23,

Losing power 5 times since June 23 2015 is completely unacceptable.

Can you describe to us your loss-of-drive incidents in more detail?

Everything went dark? Or all the lights came on in your instrument panel? Or car jumped to Neutral from D? What error messages did you see before and/or after your loss-of-drive? At what speed were you driving? What model year is your car? Which state are you in?

p.s. Yes, you should ask them to make sure you have the latest firmwares for all three control units.
 
Hi Tom,

I have the 2015 B class with the premium package and am in Orange County, CA. This has happened both at high speeds on the freeway and at low speeds on back streets. I usually drive in D+ mode, but this has also happened in D auto. There's no error message displayed before or after these incidents. The car does not shift to neutral. It stays in drive, but you feel as if you're in neutral because the gas pedal does nothing. Everything doesn't go dark, but after you pull over and hit the park button, it seems as if all the dashboard lights go on (which may be the same as when you normally hit the park button. I'm usually a little stressed at this point and want to get back on the road). Once you hit power off and power on, the car goes back to normal.

My plan is to call tomorrow on Monday and see if they're aware of the firmware update. But I don't want to bring it in and have them just hold onto it for a while unless they know what the fix should be. Tom, what are the 3 control units I should be telling them need updating?

Thanks for the responses.

Chris
 
Your loss-of-drive experience sounds just like another member here a few weeks ago.

The three control units are called:

PTCU (powertrain control unit)
PTCU-GW (powertrain control unit gateway)
AAC (AC control unit)

You definitely should bring your 2015 B ED in ASAP and they will update your firmware. Please let us know of your experience after your update (say, in two or three weeks).
 
pharmama said:
Seems like there have now been at least 2 other incidents similar to mine (shows full regen) in addition to the jumping to neutral incidents.

Also interesting about one aspect of the CA Lemon Law being 30 days... my B is still at the dealer. Will be 28 days on Monday.

They told me there was a fault code (I don't know which one since I don't have service paperwork yet) which they had to consult with MB on how to address. MB told them one of the control units needed to be replaced. Took several days to get the part which apparently came directly from Tesla (which is right across the bay from us but whatever. Maybe it had to go through some bizarre Tesla-MB procurement chain). They installed the part but were waiting for confirmation from MB that they had the appropriate software versions for the new part. Days go by with them trying to verify this before they find out the person they had been working with at MB was now out of the office. At this point, they go further up the 'food chain' and consult with Germany. Germany instructs them to put in a different control unit (well, the same part but a different physical one) which they are shipping from Germany. The German part hasn't arrived yet...

Will update further when I know more.

Final (hopefully) update. I got my car back on 9/5 (took it in on 8/4 so just over 30 days). Service paperwork lists the following:
"Performed short test and found dtc's in PTCU codes U016883 and U019B83, SG-LG codes U1906F1 The control unit 'On-board charger' has an internal fault, U1907F1 The control unit 'On-board charger' has an internal faul, and U1912F1 The input current of the on-board charger is too high."

Then indicates they updated the software for the PTCU but continued to see some error messages. Ultimately were advised to replace PTCU as described above (first one from Tesla, then one from Germany) and second part has latest software.

I have not had any issues since picking up the car. However, as others have stated as well, I don't know that I can say this is a guarantee the issue is resolved. Will definitely continue to keep an eye on this thread.
 
pharmama said:
pharmama said:
Seems like there have now been at least 2 other incidents similar to mine (shows full regen) in addition to the jumping to neutral incidents.

Also interesting about one aspect of the CA Lemon Law being 30 days... my B is still at the dealer. Will be 28 days on Monday.

They told me there was a fault code (I don't know which one since I don't have service paperwork yet) which they had to consult with MB on how to address. MB told them one of the control units needed to be replaced. Took several days to get the part which apparently came directly from Tesla (which is right across the bay from us but whatever. Maybe it had to go through some bizarre Tesla-MB procurement chain). They installed the part but were waiting for confirmation from MB that they had the appropriate software versions for the new part. Days go by with them trying to verify this before they find out the person they had been working with at MB was now out of the office. At this point, they go further up the 'food chain' and consult with Germany. Germany instructs them to put in a different control unit (well, the same part but a different physical one) which they are shipping from Germany. The German part hasn't arrived yet...

Will update further when I know more.

Final (hopefully) update. I got my car back on 9/5 (took it in on 8/4 so just over 30 days). Service paperwork lists the following:
"Performed short test and found dtc's in PTCU codes U016883 and U019B83, SG-LG codes U1906F1 The control unit 'On-board charger' has an internal fault, U1907F1 The control unit 'On-board charger' has an internal faul, and U1912F1 The input current of the on-board charger is too high."

Then indicates they updated the software for the PTCU but continued to see some error messages. Ultimately were advised to replace PTCU as described above (first one from Tesla, then one from Germany) and second part has latest software.

I have not had any issues since picking up the car. However, as others have stated as well, I don't know that I can say this is a guarantee the issue is resolved. Will definitely continue to keep an eye on this thread.
Thank you for your detailed update pharmama. Wow, 30 days is a long time for them to keep your car. Hopefully they have fixed your sudden loss-of-drive problem.
 
Update:
I dropped off my B class last Monday and got it back on Thursday. Here's what they did:
Power train control unit gateway was replaced. Software updates were done.

So far so good. I'm at 4000 miles. So when I reach 6000 I'll try to re-post with an update.

I have to say that MB and particularly the gentleman, Ed, at my facility was very responsive and they had this fixed fairly quickly in comparison to what I've seen in this thread. I'm very thankful for that. It also seems as if they're getting the hang of fixing this type of situation as I'm clearly not the first and likely won't be the last with this problem.

Cheers,

Chris
 
Dumb question but I've been reading the posts about this problem of the car losing power while driving over the last couple of months. We bought (really leased it) our 2015 B-Class at the end of May, beginning of June. We've put over 3,000 miles on it and have not had a single problem with it. However, one thing I noticed in various posts is that it appears that maybe the problem is with the "premium" packages. My wife (who drives the car daily) did not want anything "fancy" and we have the very basic vehicle, no paddles, no movement assists. Could my assumption of a premium package being the problem correct? Has anyone with just the basic car package reported the problem?

JP
 

Latest posts

Back
Top