openinverter forum

I've read a lot of posts about failed inverters in Tesla drive units, and seen this happen myself. What are people doing with these drive units? It seems to me that with a failed inverter, the drive unit is useless, but also still an extremely good motor, gearbox, and differential. Is there a viable replacement inverter? Are people throwing these in the trash, or using openinverter, or something else?

Continuing your message Charlie...
I have spent a lot of time trying to locate inverters for the SDU to no avail. The only way is to buy another complete SDU, £1750 seems the norm.
We really need to have a look at repairing them or developing a similar stand alone inverter.
From what I have read and heard it seems the HV becomes shorted, if its the IGBTs / module ? are they available and if so can they be replaced ?
Could they be controlled by any other makers inverter ? What is the feasibility of that ?

Could you not remove the inverter, plate it off and use an external inverter?

Bigpie wrote: ↑Sun May 01, 2022 11:10 am Could you not remove the inverter, plate it off and use an external inverter?

You can. The only issue is that I would argue the Tesla inverter is the most powerful unit for the money. You’ll take a performance hit with just about anything else on the market. However, that shouldn’t dissuade anyone from buying a blown up one of the form factor and price is better than say a leaf or Lexus setup.

Bigpie wrote: ↑Sun May 01, 2022 11:10 am Could you not remove the inverter, plate it off and use an external inverter?

You definitely can. My question was more whether anyone actually did this, and if so, whether there are any inverters available that are sufficiently powerful and cost effective. I had a look and I wasn't convinced that I could find or build an inverter cheaply enough to make this viable.

Well, If anyone needs a working LDU inverter, I have a spare sitting on the shelf.

Well I would think that one would reuse the case and exchange the IGBTS at max. Re use the HV connectors etc. And make a board too plug-in against your SDU board..

planning to try with a volt inverter (doing a spinup of a board for it), I'll post back results.

meanwhile still working on the disassembly of my SDU, but caught up in grading finals.

Hi does anyone have one of the detachable motor mounts of an LDU left from a broken unit? The breaker yard i got the motor from is very uncommunicative, does not reply to my messages about the missing mount and is roughly 1500km far away so i can't really just go there and ask in person. (I am looking for the side mount that is bolted to the motor side)

catphish wrote: ↑Sun May 01, 2022 12:17 pm You definitely can. My question was more whether anyone actually did this, and if so, whether there are any inverters available that are sufficiently powerful and cost effective. I had a look and I wasn't convinced that I could find or build an inverter cheaply enough to make this viable.

A shop in Germany did some SDU conversions where the inverter wouldn't fit. They plated it off but still used the original Tesla inverter with cables. So at least that part works

nilsvr wrote: ↑Tue Aug 02, 2022 12:04 pm Hi does anyone have one of the detachable motor mounts of an LDU left from a broken unit? The breaker yard i got the motor from is very uncommunicative, does not reply to my messages about the missing mount and is roughly 1500km far away so i can't really just go there and ask in person. (I am looking for the side mount that is bolted to the motor side)

I have a spare. Just PM’d you.

I have a fully built and tested Combi V8 inverter which uses the Enova power stage, would that work with the Tesla motor as a test ?
Not sure if the Tesla encoder would be compatible without some interface possibly ?

Hmm interesting premise. I'm planning on putting a GS450H in my ol' Thunderbird (already have the trans/inverter) because the LDU's around here seem to be big dollars. If I could get one though with a blown inverter, preferably with the whole rear subframe, I wonder if the GS450H inverter could be made to drive a LDU? Because of course if I find a great deal on one, it'll have a blown inverter, lol

I got the impression (not real data) that the LDU inverter failures were mainly due to rotor seal failures allowing coolant intrusion, rather than a pattern of inverter failures on their own. But I haven't kept up with the topic recently. Certainly, rotor coolant seal failures are common on the older LDUs, in the RAV4EV community we see that regularly, but our RAV4EV DUs are based upon the very earliest of Tesla's LDUs and therefore experience ALL the issues those early Model S' had; it's rare to find a RAV4EV extant that hasn't had its DU replaced at least once, most under warranty.

TheSilverBuick wrote: ↑Fri Sep 02, 2022 3:55 am Hmm interesting premise. I'm planning on putting a GS450H in my ol' Thunderbird (already have the trans/inverter) because the LDU's around here seem to be big dollars. If I could get one though with a blown inverter, preferably with the whole rear subframe, I wonder if the GS450H inverter could be made to drive a LDU? Because of course if I find a great deal on one, it'll have a blown inverter, lol

Good question... I would imagine if you used a logic board you definitely could, but I think the logic board for GS450H never really came to fruition b/c the VCU came along. But if you use the VCU then I would imagine the stock Lexus inverter might not want to work properly since the encoders and overall composition of the motors are different? Also you'd only have 1 motor, it might not be happy missing MG1. Just spitballing here, I have very little knowledge of the control system of the VCU, I'm still kind of stuck in the past with the logic boards.

On the other hand are there no car scrappers in your area? Down here in South Fl I've been able to find P85D LDUs for ~$1800, straight out of the car. I had bought one for $1500, realized I was never gonna use it and sold it for profit. Most of the profit these guys make is from the batteries and body parts, say they spend $13k on an S85, they already recoup no less than $18k on batteries, everything else is profit, so they take offers on the big parts to get them out of the way. Because TBH tesla drive units (Stock, obviously) after 2015 are so reliable there's not really a market for them except for swaps, and even then the people that actually do them are few and far between.

I haven't looked in a good year, but the scrapers near here are in northern CA and they seem to want gold for every part.

Has anyone tried to take the good ones out of a blown SDU power stage and repair another? AUIRGPS4067D1 its a shame these are discontinued. or does someone want to sell their damaged one? if your in the US or Canada with a damaged unit and interested let me know please. My unit has shoot through of around 500 milliamps with a HV of 120v when the inverter is switched on, it drives the motor fine for testing on the bench but I know its just temporary.