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

[TonyWilliams]

If Toyota found it necessary to do this recall with 2500 RAV EVs on the road, it's pretty likely Mercedes will do the same (assuming the source of the problem is with the same Tesla drivetrain).

Everyone should keep a close eye on this.

Toyota / Tesla didn't volunteer to do a recall. The U.S. Government did. Please make your reports of unsafe conditions, like the speed sensor issue that causes the car to go to neutral and stop on the highway, to the link provided.

That's how it will get fixed.

https://www-odi.nhtsa.dot.gov/VehicleComplaint/index.xhtml

You can also phone the Vehicle Safety Hotline: 1-888-327-4236 / Hearing Impaired (TTY): 1-800-424-9153) for assistance. Form Approved: OMB No. 2127-0008; Expires 05/31/2018


You might mention in the report that this appears to be the same issue shared with the Tesla drivetrain in the 2012-2014 Toyota RAV4 EV "loss of speed sensor signal causes vehicle to go into neutral and lose propulsion power".

 

[TonyWilliams]

Summary of the problem of the tolerances on the speed sensor being greater than the software is happy with:

http://www-odi.nhtsa.dot.gov/acms/cs/jaxrs/download/doc/UCM474877/RCORRD-15V143-3968.pdf

 

[tom]

(deleted)

 

[tom]

Summary of the problem of the tolerances on the speed sensor being greater than the software is happy with:

http://www-odi.nhtsa.dot.gov/acms/cs/jaxrs/download/doc/UCM474877/RCORRD-15V143-3968.pdf

Everyone interested should read above PDF file from Toyota. Here is an excerpt from the document (supplier = Telsa):

November 2014 - February 2015
Additional reports were received, and the supplier continued to investigate the cause of the loss of drive power. During further investigation, the supplier determined that hardware variance is larger than firmware (software) tolerance. This can cause the drive inverter to be unable to determine the rotational position of the motor. If this occurs, a “Check EV System” warning message on the instrument panel will be triggered, a malfunction indicator lamp (MIL) will come on, and the electric motor will shift to “neutral”, resulting in a complete loss of drive power.

 

[padamson1]

Everyone interested should read above PDF file from Toyota. Here is an excerpt from the document (supplier = Telsa):

November 2014 - February 2015
Additional reports were received, and the supplier continued to investigate the cause of the loss of drive power. During further investigation, the supplier determined that hardware variance is larger than firmware (software) tolerance. This can cause the drive inverter to be unable to determine the rotational position of the motor. If this occurs, a “Check EV System” warning message on the instrument panel will be triggered, a malfunction indicator lamp (MIL) will come on, and the electric motor will shift to “neutral”, resulting in a complete loss of drive power.

So this sounds like only a firmware upgrade is needed (to increase the tolerance), not a replacement of the drive train. I suppose they could replace the offending drive train parts with something that only operates within the variance threshold of the SW (higher quality parts?), but this just means that some other part will cause a similar issue later.

 

[tom]

Everyone interested should read above PDF file from Toyota. Here is an excerpt from the document (supplier = Telsa):

November 2014 - February 2015
Additional reports were received, and the supplier continued to investigate the cause of the loss of drive power. During further investigation, the supplier determined that hardware variance is larger than firmware (software) tolerance. This can cause the drive inverter to be unable to determine the rotational position of the motor. If this occurs, a “Check EV System” warning message on the instrument panel will be triggered, a malfunction indicator lamp (MIL) will come on, and the electric motor will shift to “neutral”, resulting in a complete loss of drive power.

So this sounds like only a firmware upgrade is needed (to increase the tolerance), not a replacement of the drive train. I suppose they could replace the offending drive train parts with something that only operates within the variance threshold of the SW (higher quality parts?), but this just means that some other part will cause a similar issue later.

For now, seems like Toyota & Mercedes are swapping drivetrains if your car jumps to neutral without warning. Likely they have thought of cheaper alternatives like a firmware update if it was possible. Maybe these two auto makers don't care about the cost of the hardware because Tesla is giving them the drivetrain (under their warranty agreement). The drivetrain is $14,000 if your car is out of warranty. For MB B owners, for now, everything is on a case by case basis. RAV EV has longer history on the road.

 

[Simonb]

There is a slight difference between my B-Class and what is happening with the RAV4. On the Rav4, at least you are getting a warning light coming on when the car looses power and shifts to neutral. My B-Class, it gives you no warning at all and just shifts to neutral. The only time warning lights come on is when you finally come to a complete stop, then all of the ***** lights come like the car has stalled. When I took it to the dealer, they tell me that there are no stored fault codes. If it is a faulty speed sensor inside the drive unit, then the drive unit will need to be replaced since the drive unit cannot be taken apart to be repaired. Not even Tesla service centers take apart drive units, if there are any problems internally, in either the motor, transmission or inverter, the complete unit gets replaced. Also worth noting, Tesla extended the warranty on drive units to 8 years/unlimited mileage. Mercedes may have to think about offering something similar.

 

[tom]

There is a slight difference between my B-Class and what is happening with the RAV4. On the Rav4, at least you are getting a warning light coming on when the car looses power and shifts to neutral. My B-Class, it gives you no warning at all and just shifts to neutral. The only time warning lights come on is when you finally come to a complete stop, then all of the ***** lights come like the car has stalled. When I took it to the dealer, they tell me that there are no stored fault codes. If it is a faulty speed sensor inside the drive unit, then the drive unit will need to be replaced since the drive unit cannot be taken apart to be repaired. Not even Tesla service centers take apart drive units, if there are any problems internally, in either the motor, transmission or inverter, the complete unit gets replaced. Also worth noting, Tesla extended the warranty on drive units to 8 years/unlimited mileage. Mercedes may have to think about offering something similar.

I doubt Mercedes will do that. Big legacy auto don't have that mentality. That's one more reason no one should buy these cars, only lease, so the car will be under full warranty during the life of the 3 year lease.

The B has been out since July 2014, it is really strange why all these lost-of-drive issues showed up since June 24 2015, and all were new cars on the road with very low miles. Tony's Oct 2014 lost-of-power event don't count because that was fixed by firmware and never occurred again. I looked through this entire site and could not find any more cases of sudden lost of drive reports. The six of us on the list are the unlucky ones: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=380 Will be interesting to see what happens second half of 2015. I think you will be fine simonb, once you get your new drivetrain. So far, my stall issue is not reproducible. I'll be bring my B in next Monday to see if there was an fault code logged.

 

[phototrek]

My one time experience with loss of drive was very simple - I'm driving in E, and suddenly lose all power. No lights, no beeps, just coasting. I don't recall if the indicator showed N or D, but I lost all drive and was mainly focused on stopping at an "opportune" location and time. Since I have keyless, it's not possible that I accidentally bumped the key and thus killed drive - something that's been reported with some 2014 folks.

I stopped, put the car in Park, and restarted it. It went on fine from there.

 

[phototrek]

My one time experience with loss of drive was very simple - I'm driving in E, and suddenly lose all power. No lights, no beeps, just coasting. I don't recall if the indicator showed N or D, but I lost all drive and was mainly focused on stopping at an "opportune" location and time. Since I have keyless, it's not possible that I accidentally bumped the key and thus killed drive - something that's been reported with some 2014 folks.

I stopped, put the car in Park, and restarted it. It went on fine from there.

 

[tom]

phototrek: Yours was a 2015 B. This happened only one time after your firmware update? Did you bring your car back to the shop? What did they say? Any error codes logged? If it was only one time and not reproducible, I assume you just let it go for now, unless it happens again.

 

[phototrek]

The combination of (1) my dealer's sheer and utter complete incompetence, (2) my immediately upcoming vacation (greetings from Panama!), and (3) this having happened only once, I figured I'd leave it alone and see what happens next. Maybe there's more tea leaves, maybe it will die for good. I know that rebooting fixes it, which is clearly not ideal but it's not the end of the world, even in rush hour traffic.

 

[Senqua]

Just purchased the B-Class last night had 15 miles on the car and on the way home from the dealership on the freeway at 65 mph the car went into neutral. From the fast lane my wife had to pull over and exit on inertia alone. There was no power steering. Life flashed before her eyes.

Talk about a bad experience. Almost dying on your way home after buying a new car because the car can't drive.

I don't even wan't this unsafe car anymore if it is going to kill me and my family.

 

[tom]

Just purchased the B-Class last night had 15 miles on the car and on the way home from the dealership on the freeway at 65 mph the car went into neutral. From the fast lane my wife had to pull over and exit on inertia alone. There was no power steering. Life flashed before her eyes.

Talk about a bad experience. Almost dying on your way home after buying a new car because the car can't drive.

I don't even wan't this unsafe car anymore if it is going to kill me and my family.

Senqua: Sorry this happened to you. I added you to the list here: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=380

You should also read: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=374

For the sake of all MB B EV drivers on the road (about 1,000 of us), could you please provide us with the following regarding your car and experience:

* What model year was your MB B EV?

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

* Please describe the incident in more detail, in particular, did other lights show up on the instrument cluster when your car suddenly jumped into neutral?

* Did your car suddenly shift to neutral or did you simply lost drive? or simply lost all power? (this is important in figuring out the cause of the problem)

* Any error messages displayed on the instrument cluster?

* Were you driving on D or D+ D- or D-auto when this happened?

* Approximately where are you located?

* Did you cancel your lease? or return the car if you bought it?

* IMPORTANT: please keep us posted in the coming days and weeks as you interface with Mercedes service tech.

In addition to posting to this forum, please feel free to PM me if you have any questions.

 

[aloizi98]

Hello.

Seems like more people are having dangerous with the B-Class Electric Drive. It was a great idea for Mercedes to have an electric car, but in reality this has been a failure. Too many people have been having issues and MBUSA should strongly consider recalling these cars.

I wrote a letter to MBUSA as you know. I sent it last Saturday. Tuesday I received a call from a case manager at corporate who said that Mr. Cannon (The CEO) read the letter and he as well as his team will come up with a solution.

Thursday I got a call from the dealer who sold me the car to say I could either: 1. Come and get my repaired B-class 2. Have them get another B-Class electric for me or 3. Take "any car I want".

In my letter I asked for a gasoline powered automobile with the same MSRP. It looks like that is what I am getting.

The dealer will call me this week so I can pick it up. I won't believe they will just simply swap the car for me until it is actually in my garage at home, but this was their solution.

Of course, this completely defeats the purpose of why I bought the B-Class Electric Drive in the first place, but now with all the recalls and issues with the drivetrains with MBUSA and other companies, I am hesitant to get any electric car, particularly what I went through with my family.

Make your voice heard to MBUSA. It seems like they do listen. At least to me.

I did not cause a ruckus at the dealership. I actually praised everyone there in my letter. In this situation, I mimicked U.S. President Theodore Roosevelt's foreign policy: "speak softly, and carry a big stick".

It worked for me.

 

[tom]

Thursday I got a call from the dealer who sold me the car to say I could either: 1. Come and get my repaired B-class 2. Have them get another B-Class electric for me or 3. Take "any car I want".

Thank you aloizi, all MB B EV drivers on this forum appreciate your updates.

It's good to know MBUSA is giving people these options.

They did not give you the option to cancel your lease? Did you ask for that? Maybe you could just do that? (and if you bought your car, just undo the deal?)

No doubt sudden loss-of-drive is a very serious safety issue. Here is my rough analysis of the probability of this occurring.

I suspect there are approximately 1,000 MB B EVs on U.S. roads today, and in this list: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=380 we have 7 reported cases on this forum of sudden loss-of-drive. (I'm not counting Tony's case because that's been resolved by an firmware update in late 2014)

Of these 7, possibly 5 are due to the Tesla drivetrain-speed-sensor issue for sudden shift-to-neutral.

There are 420 members on this forum, of which I am going to guess at most half (210) actually drive this car.

Based on above info, my rough guess is of the 1,000 MB B sold, about 30 experienced sudden loss-of-drive issues, or 3%. (Note: (1000 / 210) * 7 = 33, I rounded 3.3% to 3%)

3% is a huge number for this dangerous condition (sudden loss-of-drive). Even 1% is way too high.

If we assume a third of the members here drive this car (140 out of 420), then it's possible we are looking at 5% fail rate, which is horrendously bad, i.e. one out of every twenty cars. Same math: (1000 / 140 ) * 7 = 50.

We don't know what the truth is, MBUSA has the data.

Earlier last week you said they were about to install a new Tesla drivetrain for you. Did they already put the new drivetrain in? Chances are good your B will not experience this issue again with a new drivetrain. They gave you the option to swap it for another B, but you don't want that? You have already decided to get an ICE MB?

Please keep us posted either way!

 

[Senqua]

I just wanted to post an update to my "sudden shift to neutral" issue that occurred driving the car home from the dealer on July 18th.

Today the dealer picked up the car because it's not safe to drive back to the dealer. They had me call road side assistance from my house. They gave me a loaner car.

The dealer has refused to cancel the lease.

I talked to a California Lemon Law attorney today. Since this "shift to neutral" problem could result in a condition that is likely to cause death or serious bodily injury if the vehicle is driven. The problem has to be subject to repair two or more times by the manufacturer or its agents, and the buyer or lessee has at least once directly notified the manufacturer of the need for the repair of the problem as provided in the warranty or owner's manual.

* What model year was your MB B EV?
2015 I only put exactly 25 miles on the odometer from the dealer to the car breaking down.
Hows that for quality craftsmanship?

* Which mm/yy was it made (see label on driver door frame)
I will have to check when they return the car from the shop.

* Please describe the incident in more detail, in particular, did other lights show up on the instrument cluster when your car suddenly jumped into neutral?
No other lights showed up.

* Did your car suddenly shift to neutral or did you simply lost drive? or simply lost all power? (this is important in figuring out the cause of the problem)
All acceleration was suddenly lost. Gas pedal did nothing. Yes the car was in neutral.

* Any error messages displayed on the instrument cluster?
NONE

* Were you driving on D or D+ D- or D-auto when this happened?
Just D

* Approximately where are you located?
Los Angeles

* Did you cancel your lease? or return the car if you bought it?
Dealer says I cannot cancel the lease. The foreman is going to try to repair it. We are very scared to drive it. Right now any car that does not try to kill me or my family would be great.

 

[tom]

The dealer has refused to cancel the lease.

I talked to a California Lemon Law attorney today [...] The problem has to be subject to repair two or more times by the manufacturer or its agents, and the buyer or lessee has at least once directly notified the manufacturer of the need for the repair of the problem as provided in the warranty or owner's manual.

Thank you for your update Senqua.

MB B EV and Toyota Rav4 EV share the same Tesla drivetrain (motor, firmware and battery technology)

Mercedes started selling the MB B EV in the U.S. July 2014.

Toyota sold the Rav4 EV from 2012 to 2014, there are approximately 2,500 of them on the road today.

Toyota is doing a recall because of Tesla's drivetrain issues that can cause the car to suddenly shift to neutral. But note, phase 1 of this recall was announced, but they don't yet have a fix for the problem!

May I suggest you do the following:

* You probably already have done so, read these threads thoroughly:

a) LIST: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=380
b) Lost of drive: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=359
c) Drivetrain: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=374

* MBUSA is the decision maker, so write to them. Do as your attorney suggested, create a paper trail, write to MBUSA and Cc appropriately (including your dealership, and I would suggest also include the CEO & CTO of Tesla Motors). aloizi98 wrote to MBUSA and he received the desired results.

* File your case with NHTSA:

http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=7&t=370&p=2928#p2928

* Let your dealership's service department try to: 1) identify the problem, and 2) fix it.

We can't say for sure, but based on your description of the incident, it's possible they will say you need a new Tesla drivetrain, or they will say they can't identify or reproduce the problem. Please let us know what fault codes they were able to retrieve.

* Show MBUSA and your dealership this forum and show them the relevant threads and posts.

* Educate them on the drivetrain defect and the status of the Toyota recall, especially the Toyota PDF file TonyWilliams posted on this forum. Tony is an expert in this issue and he is a very active member on the RAV4 EV owners forum ( http://www.myrav4ev.com/forum/viewtopic.php?f=7&t=1558 ).

a) Toyota's defect information report:

http://www-odi.nhtsa.dot.gov/acms/cs/jaxrs/download/doc/UCM474877/RCORRD-15V143-3968.pdf

In it, they described the sudden shift-to-neutral problem: "The Electric Vehicle Traction Motor Assembly in the subject vehicles is part of the propulsion system, which contains a drive inverter (DI), DI electronic control unit (ECU), electric motor, motor speed sensor, shift control actuator, and transaxle assembly. The motor speed sensor detects the electric motor speed and rotational position, and sends this information as a signal to the DI ECU. Due to a software issue, the DI ECU may not be able to determine the rotational position of the motor, which causes a speed sensor error code. This will trigger a “Check EV System” warning message on the instrument panel, turn on a malfunction indicator lamp (MIL), and cause the electric motor to shift to “neutral”, resulting in a complete loss of drive power. A complete loss of drive power may increase the risk of a crash."

And on page 3 they said: "November 2014 - February 2015. Additional reports were received, and the supplier continued to investigate the cause of the loss of drive power. During further investigation, the supplier determined that hardware variance is larger than firmware (software) tolerance. This can cause the drive inverter to be unable to determine the rotational position of the motor. If this occurs, a “Check EV System” warning message on the instrument panel will be triggered, a malfunction indicator lamp (MIL) will come on, and the electric motor will shift to “neutral”, resulting in a complete loss of drive power."

b) Toyota's RAV4 EV recall press release dated 3/11/2015:

http://pressroom.toyota.com/releases/toyota+recall+camry+highlander+rav4+march11.htm

c) Toyota's recall letter to RAV EV owners (sent during April & May 2015):

http://www2.dth.net/rav4ev/recall/20150504safetyrecall.pdf

Please keep us informed of your interactions with MBUSA and your dealership. Share with this forum what you learn, posting here on this forum is important because it will: 1) allow others to learn from your experience, 2) put public pressure on MBUSA, your dealership, and Tesla Motors.

 

[vakilak]

I had the very same situation happen to me and I just finished reporting it on the US DOT website (https://www-odi.nhtsa.dot.gov/VehicleComplaint/index.xhtml).

In short:

I was cruising down a pretty busy main street. As I was trying to manuever in traffic, I sensed that as I was pressing on the gas, the car was unresponsive. I looked at the dash and noticed the car had moved itself into neutral. I tried to turn the key, but nothing happened. The car was unresponsive, but still on (from the look of the dashboard). I quickly tried to coast to the side of the road, in between speeding traffic, which was very dangerous, as I was near the highway onramp area. Once I safely pulled aside, I tried to again turn the car on using the key. Again the car was unresponsive. I turned the key to the off position and pulled the key out. When in the off position, all the lights on the dash lit up. I pulled the key out and reinserted it and turned the key and the car came back on and began to drive normally.

 

[tom]

I had the very same situation happen to me and I just finished reporting it on the US DOT website (https://www-odi.nhtsa.dot.gov/VehicleComplaint/index.xhtml).

In short:

I was cruising down a pretty busy main street. As I was trying to manuever in traffic, I sensed that as I was pressing on the gas, the car was unresponsive. I looked at the dash and noticed the car had moved itself into neutral. I tried to turn the key, but nothing happened. The car was unresponsive, but still on (from the look of the dashboard). I quickly tried to coast to the side of the road, in between speeding traffic, which was very dangerous, as I was near the highway onramp area. Once I safely pulled aside, I tried to again turn the car on using the key. Again the car was unresponsive. I turned the key to the off position and pulled the key out. When in the off position, all the lights on the dash lit up. I pulled the key out and reinserted it and turned the key and the car came back on and began to drive normally.

Wow! Another one this week! That's 8 cars in the past 30 days that experienced sudden loss-of-drive!

Sorry this happened to you vakilak. I added you to the list here: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=8&t=380

You should also read: http://www.mybclasselectricdrive.com/forum/viewtopic.php?f=7&t=370

For the sake of all MB B EV drivers on the road (about 1,000 of us), could you please provide us with the following regarding your car and experience:

* What model year was your MB B EV?

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

* When did you lease or buy your car, and how miles have you driven before this happened?

* Any error messages displayed on the instrument cluster when this happened?

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

* Approximately where are you located?

* Did you cancel your lease? or return the car if you bought it?

* IMPORTANT: please keep us posted in the coming days and weeks as you interface with Mercedes-Benz.

In addition to posting to this forum, please feel free to PM me if you have any questions.