First Model 3 motor failure reported

[jsmay311]

Finally got my car back yesterday.

Does anyone else have a better understanding about the effects of a blown pyro fuse and can point out errors in my logic?

The service center tech clarified that the pyro fuse that blew was in the drive unit itself and was not the main HV battery pack fuse. So that clears some things up.

He said that Tesla Engineering told him that the vehicle logs showed that there was an (unspecified) mechanical failure inside the drive unit (which they couldn't/wouldn't specify -- he made it sound like they were purposefully withholding more detailed information), and that was followed by a voltage spike which caused the fuse to blow.

As for why the motor seemed to continue to respond to accelerator pedal inputs for a while after the initial mechanical failure... the tech that I spoke to wasn't sure, but he guessed that there might've been a few seconds between the mechanical failure and the voltage spike, and maybe the voltage spike / fuse blowing happened after the motor started spinning up.

 

[JRP3]

I suppose the fuse could have blown a while after the initial breakage, if you tried to keep getting the vehicle to move. Broken gears jamming the motor, throttle input sends current to the motor which can't turn and the fuse blows.

 

[ℬête Noire]

Finally got my car back yesterday.



The service center tech clarified that the pyro fuse that blew was in the drive unit itself and was not the main HV battery pack fuse. So that clears some things up.

He said that Tesla Engineering told him that the vehicle logs showed that there was an (unspecified) mechanical failure inside the drive unit (which they couldn't/wouldn't specify -- he made it sound like they were purposefully withholding more detailed information), and that was followed by a voltage spike which caused the fuse to blow.

As for why the motor seemed to continue to respond to accelerator pedal inputs for a while after the initial mechanical failure... the tech that I spoke to wasn't sure, but he guessed that there might've been a few seconds between the mechanical failure and the voltage spike, and maybe the voltage spike / fuse blowing happened after the motor started spinning up.

It could very well be that the engineers have some strong suspicions but don’t want to be on record until they open it up to figure out the true root cause & chain of events.

It can be hard to provide a clear, detailed & accurate explanation to a layperson level when there are still unknowns.

 

[viperssd]

Failure analysis almost always requires the actual part to actually get to root cause. Everything until the parts are analyzed are purely speculation.
That being said, something internal like a gear breaking would definitely cause an over-current situation as the motor is trying to maintain speed and position.

 

[ngogas]

No big deal. Under warranty.

 

[cclcal]

Unfortunately this happened to our Model 3 today, 2200 miles.
All these warnings came on, regen braking, traction control, emergency braking all disabled then a loud clunking sound and car lost all power and we had to slowly make it to side of freeway. Resetting, rebooting did nothing. Towed to Tesla, they saw rear drive unit failure.

Great...

Not happy right now.

 

[Jedi2155]

Unfortunately this happened to our Model 3 today, 2200 miles.
All these warnings came on, regen braking, traction control, emergency braking all disabled then a loud clunking sound and car lost all power and we had to slowly make it to side of freeway. Resetting, rebooting did nothing. Towed to Tesla, they saw rear drive unit failure.

Great...

Not happy right now.

Think on the bright side....you'll likely get a Model S loaner for a week or 2 which normally comes only after 3 qualifying referrals.....

 

[Oyinko]

Mine failed after only 126 miles

I've been driving a loaner Model S since almost 3 weeks...

 

[Jedi2155]

I was doing a cost calculation for my car and my per mile wear and tear is likely between $0.36 to $0.42/mile. I have an almost typical SoCal daily commute of 60 miles + 200 miles of weekend driving, I'd be saving almost $300-400 over the time I'm driving a loaner vs. my own car.

 

[run-the-joules]

Think on the bright side....you'll likely get a Model S loaner for a week or 2 which normally comes only after 3 qualifying referrals.....

I think it's 4 referrals now. One of those things I"d like to get to eventually so I can do a road trip in someone else's car.

 

[Lozza12]

Unfortunately this happened to our Model 3 today, 2200 miles.
All these warnings came on, regen braking, traction control, emergency braking all disabled then a loud clunking sound and car lost all power and we had to slowly make it to side of freeway. Resetting, rebooting did nothing. Towed to Tesla, they saw rear drive unit failure.

Great...

Not happy right now.

This is always upsetting when it’s your pride and joy and you want the car to be the best thing ever.

Remember that starter motor failures occur in ICE cars as well, so the technology is not infallible or a problem unique to Tesla.

 

[ChrisH]

Ugh. At what point is the “early failure” considered over. I’m just over 1550 miles in almost three months and thought I might have been in the clear by now.

 

[Linkeds2]

I bought a Ferrari 308 in the 1980s and the one thing I expected was a tough engine (after all the endurance racing etc..)

Within 500 miles I needed a new engine as the original was drinking oil! Freak incident?

I understand that if electric motors last the initial period then they run 'forever'. We used to have brand new electric motors on air conditioning equipment fail within days (or not at all..)

Engines 101: break in engines first before you run them hard

 

[BioSehnsucht]

Engines 101: break in engines first before you run them hard

This used to be very true, though it's less true now. I still wouldn't rag on new ICE for at least a few hundred miles, and maybe also avoid running it at one constant speed, but as long as you're not driving like a madman it's probably fine.

 

[cclcal]

Think on the bright side....you'll likely get a Model S loaner for a week or 2 which normally comes only after 3 qualifying referrals.....

very true. I have been giving a S 75D loaner. I guess it's always better to put miles on someone else's car. But I am making payments on the M3.
The service advisor said should be good to go next week....we will see

 

[Jedi2155]

very true. I have been giving a S 75D loaner. I guess it's always better to put miles on someone else's car. But I am making payments on the M3.
The service advisor said should be good to go next week....we will see

My car is currently under service work due to tire damage too. I calculated my per mile cost based on a 200,000 mile life is somewhere between $0.36 to $0.42 depending how I do my cost calculation. Basically my daily drive to work costs me at least $20 in depreciation (assuming zero value at 200,000 miles which isn't technically true).

Making payments on the 3, but keep in mind the warranties are mileage based as well so I'm saving on that.

 

[cclcal]

My car is currently under service work due to tire damage too. I calculated my per mile cost based on a 200,000 mile life is somewhere between $0.36 to $0.42 depending how I do my cost calculation. Basically my daily drive to work costs me at least $20 in depreciation (assuming zero value at 200,000 miles which isn't technically true).

Making payments on the 3, but keep in mind the warranties are mileage based as well so I'm saving on that.

very true. I feel a little better.
I wonder if there is stats of motor/drive unit failures. Im Rear drive unit is the motor?

 

[ChrisH]

very true. I feel a little better.
I wonder if there is stats of motor/drive unit failures. Im Rear drive unit is the motor?

I think the failure rate is higher than a lot of people on here like to admit but I have no proof. I kind of wish I had bought a dual motor so I wouldn’t be stranded if my one rear motor fails.

 

[cclcal]

I think the failure rate is higher than a lot of people on here like to admit but I have no proof. I kind of wish I had bought a dual motor so I wouldn’t be stranded if my one rear motor fails.

haha, I remember Musk tweeting that. I remember thinking you have that little faith in the car you built? What are the odds the motor will fail? I never bought an ICE car worrying about the engine, thinking there should be two under the hood.

Musk is a very smart man, he knows exactly what he is talking about. He gave us fair warning, you should get the dual motor in case one fails.....my fault for not obeying him

 

[ChrisH]

haha, I remember Musk tweeting that. I remember thinking you have that little faith in the car you built? What are the odds the motor will fail? I never bought an ICE car worrying about the engine, thinking there should be two under the hood.

Musk is a very smart man, he knows exactly what he is talking about. He gave us fair warning, you should get the dual motor in case one fails.....my fault for not obeying him

Ya. Annoyed I didn’t get the dual motor. Wish they would figure out the drive motor issues though. At first I really thought I made the wrong choice in buying EAP over AWD/dual motor but EAP really is convenient and I’ve learned to appreciate it more.