EME swap, possibilities?

[Brettfcars]

Hi all,
I have a 2015 i3 with Rex.

If it turns out my EME is bad, I understand I could fit a secondhand replacement swapping the coms board.
That way no programming is required, providing the fault is seen in the swapped main unit.
Investigation finds a big change in late 2016 when some charging electronics was altered.
Also the Rex and Bev models have different part numbers for the EME.
I have seen that higher rated batteries are being swapped in with no mention of a EME swap, just a reprogram.
So it would appear the battery size doesn’t matter.
Part number checks finds EME with Rex up to late 2016 are a match. However is it due to the pre-programming done by BMW, which swapping the coms board would resolve.
I think I read that a non-Rex could be used in this situation as no internal differences, but I can’t refine that link.

So 2 questions
1. What EME’s are an option to use to swap in my coms board ?
2. Is it feasible to remove the EME by lowing engine rather than complete removal.

Merry Christmas all

 

[Brettfcars]

I am finding out the following answers to my questions.

1.

Checking a part supplier and cross referencing finds the following Parts numbers to be usable. There were a few updates throughout the production.

This is the list for the 1st gen 60Ah version.
They all start with 1236 then…
8688834, 8679694, 8652056, 8644793, 8642609, 8642558, 8630201, 8630199, 5A38758. (Last one is current stock).

Bev version numbers are different, but is it just initial programming ?

Bev version numbers are, 1236 86888333, 8679693, 8652055, 8644792, 8642608, 8642557, 5A38757

Looking at the above the numbers for the Rex are always 1 number higher.

2.

I have found a link where it is stated that removing the left hand engine mount, removing the HV cable and lowering the engine gets it low enough to remove the cover screws. And perhaps discover the fault. The Motor Rotor wiring and motor controller are also possible to swap.

Also I find the motor rotor cover looks removable once the engine mount is off. This surges the EME May be removable as all bolts and fixings are reachable?

 

[Brettfcars]

Has anyone opened a EME and have knowledge of internal differences?
Or have photos.
Would like to know if just initial programming or physical differences.
As mentioned I have see people state battery upgrades, without saying the EME was replaced, but it was set up for the higher capability.

Thought's or links to info are appreciated.

Regards
Brett

 

[alohart]

Have you contacted Auto-Tec Diagnostics in Norfolk? They seem to have significant EME knowledge. I don't know how much of that they would share with you, but you're fortunate to have a facility relatively close by who could probably answer your questions.

 

[RP67]

I've replaced my EME on my 2014 rex, by swapping the control board out.


This is my original EME



I had the replacement which is the same year




I also had the chance for check the newer, 2016 version inside (by getting the wrong one), which was clearly different then the two others




The CTRL board is pretty much looks the same, but surely they are not interchangeable, however I didn't even tried it.

To answer your other question, with the non REX version you can get away without disconnect the drive shafts and lower the drive train, Here is a guy who did it recently, he might join this thread later. As I have the REX version I had to lower the whole assembly, that's why I didn't do experiments. I made it quite exciting to myself anyway, due to a partially plugged in HV cable to the KLE. Took me quite some time to figure it out.
Otherwise the swap was straight forward and solved my AC charging issue.

 

[Brettfcars]

Thanks for interesting post,

I think that a charging circuit was removed from the EME after or at the beginning of 2016, and it ties in with the KLE changing as well. The KLE are noticible physically different.
I am attempting to source a early EME and hope to swap out without completely removing the drive assembly.
It looks plausible.
It may not have to come completely out if issue seen on removing the top cover…..

What was your fault. Mine simply displays a short circuit warning and rotor implausible signals. And I belive this stops the main HV from functioning .
The rotor wiring under hard to remove cover tests ok, so thinking the motor control and measurement side is faulty.
One engine mount is off already !
Car was initially laid up due to a faulty water pump, and initial ISTA scan showed some high temp warnings. These cleared. Front rad fan was working continuously, once pump fitted it now only works if commanded.
Wonder if something cooked ? And notice the motor control electrics are water cooled within the EME and look swappable.
A/C is still charged, but I will try to test out the compressor and heater to rule out again damaging a replacement EME.

Interestingly i notice your part number is not in the list I posted, but the replacement one is.

 

[3rigel]

Some great info in this thread which has helped me as I'm on a similar journey.

Have you found a replacement EME?

 

[RP67]

Thanks for interesting post,

I think that a charging circuit was removed from the EME after or at the beginning of 2016, and it ties in with the KLE changing as well. The KLE are noticible physically different.
I am attempting to source a early EME and hope to swap out without completely removing the drive assembly.
It looks plausible.
It may not have to come completely out if issue seen on removing the top cover…..

What was your fault. Mine simply displays a short circuit warning and rotor implausible signals. And I belive this stops the main HV from functioning .
The rotor wiring under hard to remove cover tests ok, so thinking the motor control and measurement side is faulty.
One engine mount is off already !
Car was initially laid up due to a faulty water pump, and initial ISTA scan showed some high temp warnings. These cleared. Front rad fan was working continuously, once pump fitted it now only works if commanded.
Wonder if something cooked ? And notice the motor control electrics are water cooled within the EME and look swappable.
A/C is still charged, but I will try to test out the compressor and heater to rule out again damaging a replacement EME.

Interestingly i notice your part number is not in the list I posted, but the replacement one is.

I had no AC charging. Apart from that was all good. DC charging fine, rex was also kept the SOC. When I was "fighting" with my phantom fault (loose HV cable), I had random faults, like temperature reading was 1000 degrees etc. That was even worse when I left the external power supply off for testing. So don't worry about random faults just yet. Get a replacement EME swap it and get back to testing after that.

 

[Brettfcars]

Hi,
Weather, Christmas, and work have stopped play but l hope to resume removal of my EME Friday.
It will be interesting to see inside and Hopfully see a fault not related to the coms board.

All photos and RP67’s comments on the later boards being different, certainly looks to be the case in photos showing the top.
I wonder if there are differences on the bottom boards, where I understand a large fuse can be found for the A/C and heater element.

I would appear sourcing there are more later EMEs avalible second hand than early ones. So being careful when looking to purchase. Also second hand listings seem to nearly always state the fitment to be 2013-2022 i3 when this is incorrect.

A cheep late EME would be hood to strip down and compare parts with……..

 

[Mondomensch]

second hand listings seem to nearly always state the fitment to be 2013-2022 i3 when this is incorrect

Yes, this seems to be a common issue. I've learned to get the item's actual BMW part number and then check that on official bmw sites.

 

[3rigel]

The one I'll be listing on ebay soon is 8630199 if its of interest.

 

[Brettfcars]

Is it know what internal parts are different between the years and EME versions ?

Are all the bottom cased parts the same ?

Ebay is being watched for parts…..

 

[RP67]

There are some pictures from the bottom. This is the 2016 unit



And here is the 2014 :








I hope this help, but to be fair, it would be a trial and error to mix and match the two different unit.

 

[3rigel]

Thanks PR67. I've struggled in the past to get info on the EME internals this is really useful. I've currently got a 2018 BEV EME in my 2014 just to see what error I get while I try and find the correct year version. Although it's not cleared and coded I can tell it's close with only a few errors. If I put a Rex unit in even though it the right age the i3 knows it a hybrid unit and tells me so on the main display. This is all great info and hopefully will help others in the future.

Cheers

 

[3rigel]

Sorry RP67.... Darn you dyslexia

 

[RP67]

Thanks PR67. I've struggled in the past to get info on the EME internals this is really useful. I've currently got a 2018 BEV EME in my 2014 just to see what error I get while I try and find the correct year version. Although it's not cleared and coded I can tell it's close with only a few errors. If I put a Rex unit in even though it the right age the i3 knows it a hybrid unit and tells me so on the main display. This is all great info and hopefully will help others in the future.

Cheers

No worries. You are the one who had the car without EME? I'm not sure if I'm right, but getting the EME "virginised" might sort out your problem, as the relevant data would be entered by your car after installation. Your fault might be only present because of the wrong data in the EME. The EME serial numbers has a massive overlap between manufacturing years and I think the main divider is the LCI which is not compatible retrospectively. There is one Chinese company what I found, they are offering the virginisation service, you only have to send the CTRL board over. It takes about 8-12 weeks though... and the chance for bricking the unit is still there.

 

[3rigel]

No worries. You are the one who had the car without EME? I'm not sure if I'm right, but getting the EME "virginised" might sort out your problem, as the relevant data would be entered by your car after installation. Your fault might be only present because of the wrong data in the EME. The EME serial numbers has a massive overlap between manufacturing years and I think the main divider is the LCI which is not compatible retrospectively. There is one Chinese company what I found, they are offering the virginisation service, you only have to send the CTRL board over. It takes about 8-12 weeks though... and the chance for bricking the unit is still there.

Yes, I'm the one with an i3 without eme. The one I've taken out of the Rex I have dismantled was a good one so Its a risk to try and virginise it without being 100% so to I thought selling and buying a BEV version was more sensible.

On the virginising front I'm looking into how we can make this a bit more accessible. It's all a bit of a long shot from someone who has little experience in this area but if I'm correct the ISN is on the Max 2 epm570 chip

 

[3rigel]

 

[3rigel]

Info I think I have so far is that it's jtag protocol and the pins to use are 22, 23, 24 and 25 For TMS TDI TDO plus ground and vcc. Programming is not my strong point so it's all a bit of a wing and a prayer. I've found a usb to jtag cable on ebay. The bits I'm missing at the moment is the jtag software, knowing which lines from the hex file contain the ISN should I be able to download the file in the first place and plenty of luck.

 

[RP67]

Info I think I have so far is that it's jtag protocol and the pins to use are 22, 23, 24 and 25 For TMS TDI TDO plus ground and vcc. Programming is not my strong point so it's all a bit of a wing and a prayer. I've found a usb to jtag cable on ebay. The bits I'm missing at the moment is the jtag software, knowing which lines from the hex file contain the ISN should I be able to download the file in the first place and plenty of luck.

Well, I wish you luck with that. Surely once you figured it out, it will be a great source of income... Using BMW explorer is probably easier and I would rather go with that. But to be fair this whole thing is very far out from my comfort zone.