2018 EME into 2015 - Also need 2018 EDME?

[ronbot]

This will certainly be a very technical question for someone out there who has serious understanding of the i3 communications traffic and logic.

My 2015 BEV has the Drive Motor Bad Bearing issue that's plaguing more and more early / high-mile i3's. BMW refused to offer any more than 15% "helps", so I'm doing it myself.

I purchased the entire electric drive assy, with EME, from a 2018 i3 s Rex with 21k miles.

Who (what module) commands the EME... is it just the EDME? If so, is it the EDME that gets coded for "s" performance?

I plan on swapping both motor & gearbox as they sit, without disassembling anything... but I know the motor position encoder "calibration" value likely gets stored in the EME, and since it's had a few additional updates, I'd rather leave the EME attached as well when installing it into my car.

I know the 2018 also brought in the much improved traction control and stability control, since they moved those functions to the EME... so it's drastically faster in those regards.

That means that the controller whose previous job was to handle those functions, will now have to have newer software. Again, this seems to be EDME's job, but I'm inexperienced in this area.

I'm an old DIY car guy, started wrenching in the mid 70's... and eventually ended up as a career EE... so I have experience in both domains.

The place I got the drive assembly from still has the donor, so I may be able to get modules from the same car, if that matters. I say that because I have heard that some modules are VIN coded, not sure if that affects anything I'll need or have.

Disclaimer - I realize that the increased 's' HP will be an increased drain on my 60Ah pack, but in all honesty, it's only a 6.5% increase... I'm not too worried. Maybe it will eventually push me to swap 94Ah modules into my pack... another issue for another day.

Whew! long post... but it covers some things others have wondered for several years.

 

[alohart]

Check your private messages.

 

[ronbot]

Haven't yet pulled the trigger on the complete 2018 drive assembly... after reading that the 2017+ model year EME - had the charging module removed and put in the KLE.

This also changed the LIM charge controller and of course the KLE itself, meaning I would have to change all of those to use a 2018 EME in my 2015.

Can anyone verify this?

If so, I may, reluctantly, back up and just use my existing 2015 EME... so the only thing I'd be gaining is a new-ish motor and gearbox.

... unless that was the end of anything else I'd have to change to make it all 2018 software compatible... except for the battery pack itself... ugh.

 

[ronbot]

I know, I've heard it before... just fix the 2015, sell it and buy a 2018... and maybe that's the best solution, but convincing my wife to buy another i3 that has definitely not been the "ideal EV" (after this expensive failure) won't be easy.

I keep hearing talk about getting a Model 3... and be just like every. other. EV. owner. in these parts...

I hate being like every other anything... I like being different! I like driving this very lightweight CRFP car that 99% of the people around here have no clue about what it is... especially after I de-badged it... other than the BMW roundels!

 

[Difid1967]

As for the calibration of the motor position encoder, it is likely that this value is stored in the EME. If you plan to swap the entire electric drive assembly, it is probably a good idea to also swap the EME to ensure that all the components are properly calibrated and communicate with each other. Regarding the VIN coding of the modules, it is possible that some modules are coded to the specific vehicle they were installed in geometry dash lite. This may affect your ability to swap modules from the same donor car, but it is unclear without further research.