Model 3 Motors on the Tesla Parts Catalog

[EVMike3]

Looking at the parts catalog released by Tesla they only show 1 motor for the rear and 1 motor for the front on a dual motor car. There is no mention of different part numbers based on the variant of the car such as RWD, AWD non-p, AWD P or AWD P with PUP.


Maybe more info will come showing different motors but at the moment they are only showing 1 part number for a rear motor and 1 part number for a front motor.

Rear Drive Unit

ASY,3DUR,MOSFET

Only for VINs with 75 kWh (E3) battery pack, Option Code BT37. Comes pre-filled with oil

Part # 1120980-00-D


Front Drive Unit

ASY,3DU, Front DU, IGBT-HC

For all AWD M3 cars. Only to use as Front DU

Part # 1120960-00-E

 

[AlanSubie4Life]

As we know, Elon says the Performance motors are binned, and so far nothing indicates that is not true (in spite of all the reprogrammed cars, etc., and all evidence to the contrary).

The traction inverters are integrated into the drive unit, and that's clear from the part details above.

Presumably what is binned is the Silicon Carbide MOSFET traction inverter in the rear drive unit ("MOSFET"). I can't imagine that there is too much sigma on the windings of a permanent magnet motor (I mean, wire is wire...probably an oversimplification, but it seems like it could be well controlled), but definitely there's going to be some manufacturing variance on SC MOSFETs' drive current.

I guess Silicon Carbide MOSFETs are more efficient than Insulated gate Bipolar Transistors (the IGBT-HC in the front drive unit).

A source discussing (there are other papers too but this was the easiest to pull up without IEEE access):
https://ecee.colorado.edu/~rwe/papers/WiPDA16.pdf

Again, continuing to go with the stated Elon fact that the motors are binned, I wonder how they distinguish them? Perhaps they're serialized and there is a database indicating the current drive performance of each motor? Must be a bear to request a binned motor for the service department, and ensure that it really is binned for a motor replacement on a Performance model, but maybe they have a lookup utility. At least Tesla has shown that they're really good at keeping all this sort of stuff straight.

 

[EVMike3]

I agree on how to keep this straight for a motor replacement. Having a different part number is one way which is why I found it interesting that they only list 1 part number. They could use a suffix on the part number. Who knows..

 

[hBomb]

Occam's razor - Simple English Wikipedia, the free encyclopedia

 

[AlanSubie4Life]

At the moment I'm content with binned motors being reality, as that requires zero new assumptions.

 

[Kirby64]

So, who's going to be the first person to do a RWD -> P-AWD DIY mod?

Sounds to me that it's pretty easily doable (assuming you can figure out the software side of things). I guess, worst case scenario you can rip the ECUs out of a wrecked P-AWD and add the front drive unit/inverter/etc. Either way, pretty intensive. I bet it'll be done though.

As far as I can tell, the main differences are (from LR RWD -> P-AWD):
* Added front drive unit and inverter stack
* Misc HV cabling to handle all the FRU
* New front axles to replace non-driven ones
* Software?

Honestly, further down the road I bet it wouldn't be that bad of a mod. All you need is a P-AWD that is totaled in a back end collision. Should keep the main bits you need in tact.

 

[Knightshade]

At the moment I'm content with binned motors being reality, as that requires zero new assumptions.

It requires assuming they're using an overly complex method of insuring replacement DUs for P models are correct- instead of simply making them a different PN after binning like a sane person would do. It would also require assuming -every- person who got an AWD at delivery and had it flashed to be a P was lucky enough to have gotten the 'right' binned motors too and someone just "forgot" to flash the software on every single one.... (and that the couple folks who ordered AWD and got a P- likewise got lucky to get "special" P motors AND someone accidentally flashed the P software too).

Versus a situation where they intended to bin at first but in actual testing they noticed all motors were good enough to go into a P so they didn't bother complicating the parts chain with unneeded extra PNs, and that in reality every DU is identical to every other DU regardless of which version of the LR 3 it goes into, and DU-wise P is just a software unlock of the AWD.

Occam's razor indeed.

 

[Kirby64]

It requires assuming they're using an overly complex method of insuring replacement DUs for P models are correct- instead of simply making them a different PN after binning like a sane person would do. It would also require assuming -every- person who got an AWD at delivery and had it flashed to be a P was lucky enough to have gotten the 'right' binned motors too and someone just "forgot" to flash the software on every single one.... (and that the couple folks who ordered AWD and got a P- likewise got lucky to get "special" P motors AND someone accidentally flashed the P software too).

Versus a situation where they intended to bin at first but in actual testing they noticed all motors were good enough to go into a P so they didn't bother complicating the parts chain with unneeded extra PNs, and that in reality every DU is identical to every other DU regardless of which version of the LR 3 it goes into, and DU-wise P is just a software unlock of the AWD.

Occam's razor indeed.

Agreed that it makes sense that it's really the same motor. Different part numbers would dictate something different.

From Ingineer's teardowns, it sounds like they're just limiting the rear inverter to 500A for the AWD models. From what I can see, the part number is still the same between all models. RWD and P-AWD get the full 800A to the rear inverter. All front inverters also get 500A.

I wonder if that means software-wise it's easier to go RWD -> P-AWD... I assume RWD you have to activate the front one anyways, which may be trickier. Or it's probably the same challenge for AWD upgrade vs. RWD, just it's all software...

 

[Knightshade]

Agreed that it makes sense that it's really the same motor. Different part numbers would dictate something different.

From Ingineer's teardowns, it sounds like they're just limiting the rear inverter to 500A for the AWD models. From what I can see, the part number is still the same between all models. RWD and P-AWD get the full 800A to the rear inverter. All front inverters also get 500A.

I wonder if that means software-wise it's easier to go RWD -> P-AWD... I assume RWD you have to activate the front one anyways, which may be trickier. Or it's probably the same challenge for AWD upgrade vs. RWD, just it's all software...

It's the same inverter. (as you can also tell by part number) on ALL rear DUs, and the same one on ALL front DUs. (for LR cars... the MR car actually has different parts in a number of places that seem to be intended for the SR eventually- which is why it has the same performance as the SR car)


Any limitations on power are entirely in software.

Hence there's no challenge at all to go AWD->P, just update the software (as numerous folks had done when their ordered P arrived as AWD).

RWD->P won't work as you're missing an entire drive unit of hardware.

 

[AlanSubie4Life]

It requires assuming they're using an overly complex method of insuring replacement DUs for P models are correct- instead of simply making them a different PN after binning like a sane person would do. It would also require assuming -every- person who got an AWD at delivery and had it flashed to be a P was lucky enough to have gotten the 'right' binned motors too and someone just "forgot" to flash the software on every single one.... (and that the couple folks who ordered AWD and got a P- likewise got lucky to get "special" P motors AND someone accidentally flashed the P software too).

Ha. The people who got P- instead of AWD -- I didn't know about that. That's funny. I'm just saying that for sure the traction inverters WILL have manufacturing variance. It may be that they're all good enough. Another possibility (similar to what you're saying, but slightly different) is that MOST motor/inverter combos are good enough to meet the P-spec. The inferior parts are serialized as such and only go in AWDs now (wouldn't be inconsistent with Elon's tweet). That would explain the P- instead of AWD scenario occurring.
I don't know anything about the details of the motor/inverters and whether they have a connection to the vehicle bus...but if there's EEPROM or e-fuse in the inverter boards, it wouldn't be out of the question for it to have a part ID indicating what sort of motor/inverter combo it was. And then the software would configure according to the indicated motor/inverter combo. I mean it is possible...
Still does seem like a very complicated inventory management issue though!

I'm just working on constructing the alternate reality here. Have to do that until Tesla comes out and says, no they're actually all the same! Just to avoid cognitive dissonance. I just have to keep drinking that delicious Kool-Aid.

 

[Kirby64]

It's the same inverter. (as you can also tell by part number) on ALL rear DUs, and the same one on ALL front DUs. (for LR cars... the MR car actually has different parts in a number of places that seem to be intended for the SR eventually- which is why it has the same performance as the SR car)


Any limitations on power are entirely in software.

Hence there's no challenge at all to go AWD->P, just update the software (as numerous folks had done when their ordered P arrived as AWD).

RWD->P won't work as you're missing an entire drive unit of hardware.

I guarantee we'll see someone do a RWD->P conversion unless the software modifications proves too complicated. From the parts list, it's just a new front drive unit and associated hardware. There's not a modified frame or anything that gets in the way. Sure, it'll be expensive, but I bet it won't be $15k expensive...

 

[Glamisduner]

It's the same inverter. (as you can also tell by part number) on ALL rear DUs, and the same one on ALL front DUs. (for LR cars... the MR car actually has different parts in a number of places that seem to be intended for the SR eventually- which is why it has the same performance as the SR car)


Any limitations on power are entirely in software.

Hence there's no challenge at all to go AWD->P, just update the software (as numerous folks had done when their ordered P arrived as AWD).

RWD->P won't work as you're missing an entire drive unit of hardware.

So they should have no issue refunding 5k of the 11k more I paid for the software update right?

 

[Knightshade]

I guarantee we'll see someone do a RWD->P conversion unless the software modifications proves too complicated. From the parts list, it's just a new front drive unit and associated hardware. There's not a modified frame or anything that gets in the way. Sure, it'll be expensive, but I bet it won't be $15k expensive...

Frame doesn't change, but suspension does (the front half shafts have to go somewhere that doesn't exist on the RWD setup IIRC)

If the software is hackable (which I imagine it is as long as you're ok with no future OTA updates and no warranty service) it'd be tremendously easier to do it to an AWD than a RWD... (and probably cheaper since it's not like Tesla will sell you a front DU anyway you'd have to buy yourself one out of a wrecked Tesla and hope it's ok)

So they should have no issue refunding 5k of the 11k more I paid for the software update right?

That entire matter was incredibly stupid on Teslas part no matter what the difference between models.

 

[Kirby64]

Frame doesn't change, but suspension does (the front half shafts have to go somewhere that doesn't exist on the RWD setup IIRC)

If the software is hackable (which I imagine it is as long as you're ok with no future OTA updates and no warranty service) it'd be tremendously easier to do it to an AWD than a RWD... (and probably cheaper since it's not like Tesla will sell you a front DU anyway you'd have to buy yourself one out of a wrecked Tesla and hope it's ok)

...

People have been doing drive pulls to upconvert Model S's all the time using wrecked parts. Not sure it'll be too bad. Also, replacing suspension components isn't too bad. Since you have to pull axles to begin with, doing suspension at the same time isn't the end of the world. It's all just a matter of finding the properly wrecked PAWD. Since any battery/frame damage pretty much totals Tesla's, I imagine front drive units won't be too hard to come by. Not easy, but not impossible. Especially if AWD parts are the same. Then you just need to find either a wrecked PAWD or a wrecked AWD.

I'm more just interested in someone converting a RWD to an AWD. P or not...

 

[AlanSubie4Life]

I did some poking around with search to see if this information was news before posting, but since it didn't show up in the search results before I got to this thread, here goes...don't blame me if "drive unit" wasn't a good enough search term to use...

There are now three different rear drive units listed in the part catalog.

Notably there appears to be just one rear drive unit in the list specifically for the AWD. And still just one drive unit listed for the front. I'm sure they're both specially binned in my P3D+ though. This makes me nervous since my front unit makes some odd moaning noises between 35 and 40 mph (noticed it right after driving away after delivery, it hasn't changed, maybe it's normal and associated with the "beeping" that some speak of). But I'm sure it's fine and if anything goes wrong I'll get one of the super special Performance motors to replace it.

Anyone know what the -LC means? It appears it could mean "low gate charge" for the switching FET, but not sure.



ASY,3DUR,MOSFET
1120980-00-D
Contact Tesla


ASY,3DUR,IGBT
1120970-00-D
Contact Tesla


ASY,3DUR,AWD,MOSFET-LC
1120990-00-A

Front:

ASY,3DUF

 

[AlanSubie4Life]

Any comments from anyone here on this discussion, now that we know there are three different rear drive unit part numbers? Any thoughts on how these might be distributed amongst different models? (I could not see that info on the parts site last time I looked.) Do we need to revisit our assumptions about the P3D and AWD part numbers? . @Knightshade (Hoping that gets some responses...) I guess I need to crawl under the car and remove my aero shield and look for a part number label to remove some uncertainty here! But only if someone agrees to do it for an AWD! Or has someone already done this?

I assume one of these DUs is for the MR. But not sure what the reason would be for the two other part numbers, given prior opinions on this topic...

 

[mike123abc]

Maybe they finally decided to source a lower priced rear motor assembly for the AWD cars. It looks like at first they used the same part and software limited. Probably because it was low priority item when they were doing anything possible to make cars. Now that the factory seems to be working well they source a new part for AWD that probably saves money... No more software upgrade to P on newer build cars...

 

[Saghost]

Any comments from anyone here on this discussion, now that we know there are three different rear drive unit part numbers? Any thoughts on how these might be distributed amongst different models? (I could not see that info on the parts site last time I looked.) Do we need to revisit our assumptions about the P3D and AWD part numbers? . @Knightshade (Hoping that gets some responses...) I guess I need to crawl under the car and remove my aero shield and look for a part number label to remove some uncertainty here! But only if someone agrees to do it for an AWD! Or has someone already done this?

I assume one of these DUs is for the MR. But not sure what the reason would be for the two other part numbers, given prior opinions on this topic...

Right at the beginning, before Tesla stripped out some details they probably didn't intend to give everyone, there were a few more details on the general public EPC. Here's a screenshot I took before they stripped the information away. At that time, they were showing two rear drive units:

It seems that the IGBT version is for the MR and SR versions. No clue what the LC is for - it wasn't in that initial EPC release.

 

[SD_MDL3]

It seems that the IGBT version is for the MR and SR versions. No clue what the LC is for - it wasn't in that initial EPC release.

Any potential longevity issues with the IGBT version in the MR car? I am getting the MR version.

 

[Saghost]

Any potential longevity issues with the IGBT version in the MR car? I am getting the MR version.

I don't think we know much about that motor. I have no reason to believe it'll be anything but reliable, but we don't have experience with it.

The only problems Tesla has ever had with drive units are the original first generation RWD S units, and as I understand it that wasn't really a motor problem but about tolerances elsewhere in the transmission assembly.