Tesla Model 3 Drive Unit Questions

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xavier847
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Tesla Model 3 Drive Unit Questions

Post by xavier847 »

I'm just starting my first EV conversion and have a rear Model 3 980 drive unit. I'm trying to decide on how to control it and have been reading into my options. This seems like great progress but I'm not too familiar with the how this would connect with the rest of the systems.

This is the Inverter board replacement for the M3/Y rear drive unit and shows it working for the front as well, would these be controlled by the drop-in logic board that's available for the other SDUs?

Would using a rear Model 3 SDU work well with a Model S front SDU? I imagine that with the logic board all the values and curves would be manually input, so there shouldn't be a conflict.

Also, is it possible to use a rear Model S rear SDU in the front? I know so far that the biggest concern would be the jackshaft that keeps the cv axles equal length to prevent torque steering and that orientation matters(rear sits in front of axle).
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Re: Tesla Model 3 Rear Drive Unit Hacking

Post by Jack Bauer »

I would advise posting your questions in a dedicated thread and doing some reading up on the OpenInverter system. Also if you have doubts in your ability please do not use this board until it is better proven in the real world and has built up some community experience.
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Re: Tesla Model 3 Rear Drive Unit Hacking

Post by hanskraayeveld »

Pretty cool stuff. Im thinking maybe Jack Bauer is the same as Damian Maguire?? :)

Youre doing great Job. Im at the moment testing to use a LDU with original inverter (immobiliser). (at the moment, I only watched CAN-traffic, so it is in a early state...)
So I have to imitate steering column (D,R,N,P), use original foot pedal (double wired) immitate some wheel speed sensors and lot of traction control traffic.

Why dont you use original, and imitate some CAN traffic? Wont it be easier?

I also did to supercharge a standalone battery pack...
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Re: Tesla Model 3 Rear Drive Unit Hacking

Post by hanskraayeveld »

The main reason why we are doing this, is we do a lot of Tesla drive unit repair (+- 50 LDU in a year).
The main problem of the LDU is coolant. We want to use a small drive unit. But tesla dont accept, because the only working setup is as 4WD. So the missing data from the front motor (ESP data) is the reason we could not replace LDU to SDU.
We are trying to fix this.
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Re: Tesla Model 3 Rear Drive Unit Hacking

Post by P.S.Mangelsdorf »

hanskraayeveld wrote: Sat Oct 11, 2025 10:52 am Why dont you use original, and imitate some CAN traffic? Wont it be easier?
This is covered extensively throughout the rest of this thread and Damien's videos. Please read through those first.
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Re: Tesla Model 3 Drive Unit Questions

Post by hanskraayeveld »

Thank you both for your warm welcome...
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Re: Tesla Model 3 Drive Unit Questions

Post by P.S.Mangelsdorf »

hanskraayeveld wrote: Sat Oct 11, 2025 6:27 pm Thank you both for your warm welcome...
Look, I'm usually the person that's welcoming and telling people to tone down the snark towards new people- you can go look through my posts for evidence of that. But when people ask questions that have been repeatedly asked and addressed, and which are exceedingly easy to find the answers to, it: a) clutters up the development thread and b) burns out the major contributors that we all rely upon. That's not speculation, it's repeatedly happened. It's not fair to them that they get burned out on these projects because new people can't/won't read before asking questions, and it's not fair to the rest of the community that these new developments get sidetracked or stalled because of it either.
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Re: Tesla Model 3 Drive Unit Questions

Post by hanskraayeveld »

Okay, it feels for me I have to say sorry... again...

But... isnt this a forum?
So you all rely on one or some few persons? "Dangerous", in my opinion.
Some guys with 4 stars, which sells some stuff which will not work, and who I have to beg to help me get it work?
Those you mean?

So if I ask them personal, they say: ask on the forum. We will not help you individual.
And if I ask on the forum, there are some ass kissers, who ask me to only read and not ask questions.

Nice here. Feels like you guys dont want me. Thanks.
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Re: Tesla Model 3 Drive Unit Questions

Post by johu »

hanskraayeveld wrote: Sat Oct 11, 2025 9:32 pm Some guys with 4 stars, which sells some stuff which will not work, and who I have to beg to help me get it work?
Those you mean?
I just checked the BMB thread and you got every help you could possibly want. After this, do you consider this language here appropriate?

You (and xavier) asked very basic beginner questions in a development thread. You should be able to handle corrective feedback to participate here in a productive manner.
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Re: Tesla Model 3 Drive Unit Questions

Post by Jack Bauer »

The purpose of asking people to use the forum for support is to publisise the knowledge so as others do not have to ask the same questrions and wait on answers. the answers are already here. It's an imperfect process of course but the more answers the better. Yes the boards I sold (Yes I am Damien) have a design flaw whereby the max chip contests the bus with Batman. A stupid error which I will correct , update the design on the repo and dump the remaining stock of boards at my cost. As I stated on the BMB thread once the Max is removed this problem is no longer present.

Not to be dismissive but the Batman board information on the website specifically states it is not a finished product but I (and others) on here have tested to the best of my ability. Also stated in general on every page is the the items I sell are not end user products.

Regards the 4 stars....I can try and remove them or ask Johu to do so if people find it offensive. I could not care less. I'm certainly not here to laud myself over others. My workshop was a cowshed in its last use.
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Re: Tesla Model 3 Drive Unit Questions

Post by P.S.Mangelsdorf »

hanskraayeveld wrote: Sat Oct 11, 2025 9:32 pm And if I ask on the forum, there are some ass kissers, who ask me to only read and not ask questions.
I never said don't ask questions. I said don't ask questions that have already been answered repeatedly. And yeah, that requires reading first, which doesn't seem like a big ask.
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Re: Tesla Model 3 Drive Unit Questions

Post by jrbe »

hanskraayeveld wrote: Sat Oct 11, 2025 9:32 pm Okay, it feels for me I have to say sorry... again...

But... isnt this a forum?
...
Nice here. Feels like you guys dont want me. Thanks.
Everyone is welcome. There's a high learning curve to getting up to speed with everything available here. The contributors are doing what they can to share their incredible work. The details can be distributed over maybe 50 pages, I get it's hard to dig through but asking for help instead of digging and learning is further straining stretched resources. It's kind of asking someone to do your project for you. Digging in helps you learn and troubleshoot things as you get into it.
They are volunteering their time and efforts unless you support them on patron or buy engineering hours.Just asking to reconsider / realign your perspective and consider it from the overwhelmed contributor.
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Re: Tesla Model 3 Drive Unit Questions

Post by hanskraayeveld »

Screenshot_20251012_164933_Samsung Internet.jpg
Its like a warm bath here...

Sorry for my behaviour... Thanks for helping me grown up.
I just checked the BMB thread and you got every help you could possibly want.
We spend 600 euro, soldered 4 chips, 2 myself, 2 by a pro, read and watched tons of "info", searched many hours for info/schematics, send many emails to Tom (without his time, it wasnt fixed yet, I think (thanks Tom!) spend a lot of time get it fixed.

Yes, I have to be very very thankfull... .
After this, do you consider this language here appropriate?
No, I would wipe my own ass, if I could reach it...

But maybe we should put our energy in other important stuff
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Re: Tesla Model 3 Drive Unit Questions

Post by hanskraayeveld »

A stupid error which I will correct , update the design on the repo and dump the remaining stock of boards at my cost.
Now they are working, and know what the problem is, I want to buy 2 more...
So please dont throw away...
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Re: Tesla Model 3 Drive Unit Questions

Post by johu »

hanskraayeveld wrote: Sun Oct 12, 2025 3:24 pm But maybe we should put our energy in other important stuff
Amen to that :) btt then
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