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Rear motor failure (on a trip out of town)

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Well, I didn't think it would happen to me even after hearing about this happen to other folks on here, but the rear motor in my car just seppuku'd while we were out of town on what was supposed to be a little bit of a weekend road trip. It's a P3D with <10000 miles on it.

Decided to take the wife and baby on a fall trip out of town to get some nice scenery. On the way there I noticed that the car started behaving a little bit strangely-navigate on autopilot would say that it was unavailable for the rest of the drive for no clear reason. Thinking back, the car had done the the day before as well but I had reset it and the message had gone away. This time though, Navigate on Autopilot would keep shutting off for the drive then randomly turn itself back on. For what it's worth I also oddly didn't get the latest firmware update-usually I get updates within the first 24 hours or so of wide release-not sure if the hardware issues somehow flagged it not to update?

Either way, about an hour and a half into the trip we decided to stop for lunch and grab some fast food. We were eating in the car when suddenly the whole car shook and I heard a loud "thunk" from the rear of the car. Initially I thought someone had rear ended us in the parking lot! I looked around and got out of the car and obviously nobody had hit the car. I was confused but we finished eating and I went to shift into reverse...and all the car started beeping and showing messages that the car was shutting down and to pull over safely and another message that the rear motor was disabled but it was OK to drive (clearly not OK to drive since it won't shift out of park).

Needless to say it had to be flat-bedded to the nearest SC. Unfortunately, the service center is in the opposite direction of where we live. But I figured I'd be able to go and get a loaner or a rental at the service center and be on our way. Yeah...turns out the service center closes very early today and would be closed just 10 minutes before the tow truck could get there.

I think OK, maybe I'll call up and see if they can wait ten minutes for me and the car to get there. By this point I'm starting to panic a bit since this service center is like a two hour drive from home. I call several times and I can't get through to anybody. So then I call roadside assistance figuring that they have some special priority number they can get through on. They call and can't get through to anybody either (seriously, they really need someone to pick up the phone at the service centers). On the bright side, roadside assistance was actually very helpful in figuring out how to get us home. Everything ended up taking quite a bit of time to set up because all the rental car places near where we broke down were closed and their original plan was to get us to Enterprise for a rental car (seriously there were like eight Enterprise locations within fifteen minutes but all of closed them at 1pm...what the heck Enterprise?!) But they set me up with Uber credits to tide me over until I can get a rental car near my home.

Now I guess I get to find out how long it takes to get the rear motor swapped on a Model 3. From what I've read it seems like the rear motor going out knocks out a fuse or a circuit of some sort from the battery. I wonder if the motor was already starting to go bad and causing other things to malfunction earlier in the drive. Now that the motor's out I noticed that the GPS location of the car no longer updates in the app and the car also seems to believe it's charging even though it isn't (it's just sitting outside in a parking lot).

At least we got lucky and had it break down in a parking lot and not while I was going 70 on the highway. Took about an hour and a half to get a flatbed to us so if we were on the side of a highway it would have been utterly miserable. Really very surprised this happened since most of the stats seem to suggest that the Model 3 powertrain is pretty reliable, but now I'm starting to wonder if the rear drive units might not be all that reliable and honestly I'm a little bit worried about taking the car on longer trips in the future. Would have really sucked if we had gotten further on this road trip before the car broken down, I'm not even sure how I would get home from 5 or 6 hours away!

Can't get the image upload function here to work but here's the error messages on imgur: Imgur

Of course now the wife is telling me that I should have just bought a boring but reliable Lexus SUV or something. Sigh.
 
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Hmm. That’s a bit strange, it sounds like the inverter suddenly failed short and presumably popped a fuse. A bit odd considering the car was just sitting.
Yeah, it is pretty strange that it just suddenly went out when we weren't even using the motor. Honestly very mysterious but I'm assuming whatever caused the failure was causing other components to not function right given the weird navigate on autopilot messages I was getting. Apparently someone else's 12V DC-DC converter went crazy when the motor failed, though I still can't explain why the drive unit would ultimately die while we're just sitting there. The AC was running but nothing crazy, maybe like 10 degrees over ambient.

It seems like dual motor cars are the most likely to fail for whatever reason since most of the failure threads I've seen were for 2018 built dual motor vehicles. I don't know if there was a bad batch of motors or what.
 
I watched a video on YouTube about top 10 most mileage model S, 8 out of 10 cars had motor replaced
Also when Elon say one of the advantages for dual motor is able to drive with one motor when the other failed, I made up my mind I just go with RWD instead
 
I watched a video on YouTube about top 10 most mileage model S, 8 out of 10 cars had motor replaced

These replacements on early Model S drive units were mostly for noise and other nuisance issue scheduled and performed at owner request. There are a low number of loss of power issues with any Tesla drive units on any vehicles ever.

YouTube has misled you in this case.
 
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Yeah your in a very very rare circle of people with rear motor failures on a model 3. As poster above stated with s/x it was a whine not necessarily a bad motor. I’ve hear very very little about motors going bad on the 3.

sorry everything was closed but like mentioned above you get a new motor!
 
Most of the early S drive units were replaced. It was due to the bearings wearing at a very high rate from eddy currents induced in the rotor having an insufficient return path. Some of this current went through the bearings and this accelerates wear considerably. They had a brush system that was apparently inadequate. So while it was effectively a design problem, it wasn’t an inverter one, and it’s resolved these days.

I would imagine this wouldn’t be an issue with 3, but it’s still kinda too new to be sure.
 
So a little bit of an update. Service center reached out yesterday, but the main news was that they’re so backlogged they couldn’t look at my car to formally diagnose it yet. So they won’t really have a formal diagnosis until likely Thursday. They did offer more Uber credits in the meantime and said they’d set up a loaner once they have a diagnosis? Not very convenient due to where it the service center is so I’m going to see if I can get a loaner sooner since I can’t really get out there the rest of the week.
 
These replacements on early Model S drive units were mostly for noise and other nuisance issue scheduled and performed at owner request. There are a low number of loss of power issues with any Tesla drive units on any vehicles ever.

YouTube has misled you in this case.

The model 3 has an oil filter that the S & X don't have. I assume it was lesson learned about sealed transmissions having little particles causing early wear and noise.
 
Most of the early S drive units were replaced. It was due to the bearings wearing at a very high rate from eddy currents induced in the rotor having an insufficient return path. Some of this current went through the bearings and this accelerates wear considerably. They had a brush system that was apparently inadequate. So while it was effectively a design problem, it wasn’t an inverter one, and it’s resolved these days.
.

My brother had a Dodge van that destroyed universal joints every 5,000 miles. Found the ground strap to the block was disconnected and every time he hit the starter the current went through the frame to the rear end and up the driveshaft where the needle bearing in the U joints arced and then to the block and starter. Went 200,000 more miles without a problem after reconnecting the ground strap to the block.
 
So they still haven't managed to get lift time to actually physically inspect the car after the car's been at the service center for a week now. I think the car is in a tow/diagnostics mode which seems to be draining the battery somewhat more aggressively so I'm a little worried it's going to drain down too much-problem is it's hard to charge since it's sorta sitting there dead so they'd have to tow it to a charger or roll it in neutral. That said, it's pretty clear what the problem is from the logs-hopefully it won't take too long to get a new rear motor ordered, it's not clear to me whether they can order the parts before they get it on the lift.

The most annoying part of all this is probably that the loaner is locked into chill mode. What a difference compared to the normal Performance mode. Since it's also a much heavier Model S the combination of the weight and Chill Mode make it feel like I'm driving the super obese version of my own car.

I've also noticed that MANY of the cars that have blown out their rear motors seem to have failures around 7000 miles. Not sure why exactly that is, but this seems to be a pretty common pattern.
 
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So they still haven't managed to get lift time to actually physically inspect the car after the car's been at the service center for a week now. I think the car is in a tow/diagnostics mode which seems to be draining the battery somewhat more aggressively so I'm a little worried it's going to drain down too much-problem is it's hard to charge since it's sorta sitting there dead so they'd have to tow it to a charger or roll it in neutral. That said, it's pretty clear what the problem is from the logs-hopefully it won't take too long to get a new rear motor ordered, it's not clear to me whether they can order the parts before they get it on the lift.

The most annoying part of all this is probably that the loaner is locked into chill mode. What a difference compared to the normal Performance mode. Since it's also a much heavier Model S the combination of the weight and Chill Mode make it feel like I'm driving the super obese version of my own car.

I've also noticed that MANY of the cars that have blown out their rear motors seem to have failures around 7000 miles. Not sure why exactly that is, but this seems to be a pretty common pattern.

Man, what a terrible experience. No excuse for them to have your car for a week without looking at it. Tesla makes great products but their service centers leave A LOT to be desired. They are still learning how to be a real car company IMO. Hope they get you taken care of soon.
 
Needless to say it had to be flat-bedded to the nearest SC. Unfortunately, the service center is in the opposite direction of where we live. But I figured I'd be able to go and get a loaner or a rental at the service center and be on our way. Yeah...turns out the service center closes very early today and would be closed just 10 minutes before the tow truck could get there.

I think OK, maybe I'll call up and see if they can wait ten minutes for me and the car to get there. By this point I'm starting to panic a bit since this service center is like a two hour drive from home. I call several times and I can't get through to anybody. So then I call roadside assistance figuring that they have some special priority number they can get through on. They call and can't get through to anybody either (seriously, they really need someone to pick up the phone at the service centers). On the bright side, roadside assistance was actually very helpful in figuring out how to get us home. Everything ended up taking quite a bit of time to set up because all the rental car places near where we broke down were closed and their original plan was to get us to Enterprise for a rental car (seriously there were like eight Enterprise locations within fifteen minutes but all of closed them at 1pm...what the heck Enterprise?!) But they set me up with Uber credits to tide me over until I can get a rental car near my home.

Very early on in my Model 3 ownership experience, my car stopped charging, I had like 40 miles range left.
Same deal - the app tried to schedule me for 2 weeks out, roadside assistance told me to drive the SC, even though I barely had the range to get there and wouldnt have the range to drive back home.

Cant talk to a real person, ever at a SC. There is no way Tesla's can be someones only car until they get this sorted out.
 
Most of the early S drive units were replaced. It was due to the bearings wearing at a very high rate from eddy currents induced in the rotor having an insufficient return path. Some of this current went through the bearings and this accelerates wear considerably. They had a brush system that was apparently inadequate. So while it was effectively a design problem, it wasn’t an inverter one, and it’s resolved these days.

I would imagine this wouldn’t be an issue with 3, but it’s still kinda too new to be sure.

Interesting, I hadn't heard the reason before. It is common in industrial motors run with a VFD drive to have this issue if they don't have insulated bearings or shaft grounding rings. I believe having an inverter duty motor reduces or eliminates this failure mode by design.