i3to2002
Posts: 14
Joined: Mon Jan 07, 2019 9:31 am

Converting BMW 2002 to electric using i3 parts

Wed Jan 09, 2019 3:16 am

Hi all,

Long time lurker, first time poster on here.

I've recently bought both a BMW 2002 from 1974 and a BMW i3 from 2016 that has been in a small-ish head on collision. My plan is to take the electric drivetrain, and as many auxiliaries as possible, from the i3 and transplant them into the 2002 in the hope of creating a really cool electric city car.

There is an enormous list of questions I have about the i3, but the main thing I'm focussed on right now is getting it running whilst it's still in one piece. The i3's airbags have deployed, the seatbelt restraints (I think also pyro) have deployed and the pyro charge on the 12v battery has fired (fixed). I think this has caused the ACSM to power down the high voltage system giving an error on the instrument cluster 'stop carefully, it is not possible to continue your journey'.

At the moment, the OBD port can't be read because the high voltage system is powered down so the OBD reader thinks the ignition is off.

My theory right now is that if I figure out how to bypass the airbag and seatbelt sensors, the ACSM will read the car as 'OK' and power the high voltage system back up.

Does anyone have any more thoughts on what could be causing the drivetrain to shutdown or what other sensors the ACSM reads?

Thanks in advance for any contributions!

Tom

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MKH
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Location: Dallas

Re: Converting BMW 2002 to electric using i3 parts

Wed Jan 09, 2019 4:50 am

Not sure exactly how the crash sensor shuts down the high voltage system, but it may just "pop" the manual disconnect, which is under the right panel under the hood. See the description on using the discontent on the "crash-card" for first responders.

https://www.bmw.ca/content/dam/bmw/mark ... 493952.pdf
Mark H.
2015 i3 Rex, Capparis White, Tera World, Technology & Driving Assistant, Parking Assistant, Harman Kardon Audio System, 19 inch 427 wheels, EVoInnovate EVSE

gt1
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Location: Baltimore

Re: Converting BMW 2002 to electric using i3 parts

Wed Jan 09, 2019 8:18 am

That sounds like a challenging project. How the battery will fit in the 2002?
Check this thread, it has links to the best available technical information: viewtopic.php?t=5444

i3to2002
Posts: 14
Joined: Mon Jan 07, 2019 9:31 am

Re: Converting BMW 2002 to electric using i3 parts

Wed Jan 09, 2019 9:32 am

MKH wrote:Not sure exactly how the crash sensor shuts down the high voltage system, but it may just "pop" the manual disconnect, which is under the right panel under the hood. See the description on using the discontent on the "crash-card" for first responders.

https://www.bmw.ca/content/dam/bmw/mark ... 493952.pdf

That's interesting, not seen that before. Just checked and my i3 doesn't have the manual cutoff under the charge port door. I assume this is a US requirement (I'm in the UK).

I got the crash sensor info from the repair manual "Two lines from the ACSM for the signal for the quick shutdown of the high-voltage system in the event of an accident of corresponding severity".

I suppose that could just be referring to the pyro charge on the 12v battery though as that is the only physical thing I know of that shuts down the high voltage components.

i3to2002
Posts: 14
Joined: Mon Jan 07, 2019 9:31 am

Re: Converting BMW 2002 to electric using i3 parts

Wed Jan 09, 2019 9:33 am

gt1 wrote:That sounds like a challenging project. How the battery will fit in the 2002?
Check this thread, it has links to the best available technical information: viewtopic.php?t=5444

I'm hoping to the put the motor/gearbox/inverter in the back and the batteries in the front.

That is a really useful link though, thanks!

theothertom
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Location: South Carolina

Re: Converting BMW 2002 to electric using i3 parts

Wed Jan 09, 2019 12:05 pm

I hate to be a "negative Nancy" but that's a quite challenging project. As you probably know, a 2002 can be a collector car. You might want to restore the 2002, sell it, and buy a new i3. Just a thought.

PBNB
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Location: Vancouver, BC

Re: Converting BMW 2002 to electric using i3 parts

Wed Jan 09, 2019 1:27 pm

There are some very interesting EV conversions done to the aircooled VW's. There is a company in California that has a kit.

http://www.evwest.com

These kits are designed for the simplicity of the old cars using some off-the-shelf components. Where as using the purpose made components in the i3 may prove challenging to fit into the old BMW.

Either way, it is sounds like a cool project!
2015 i3 REX

gt1
Posts: 321
Joined: Sat Nov 07, 2015 7:31 pm
Location: Baltimore

Re: Converting BMW 2002 to electric using i3 parts

Wed Jan 09, 2019 2:07 pm

i3to2002 wrote:
gt1 wrote:That sounds like a challenging project. How the battery will fit in the 2002?
Check this thread, it has links to the best available technical information: viewtopic.php?t=5444

I'm hoping to the put the motor/gearbox/inverter in the back and the batteries in the front.

That is a really useful link though, thanks!
The battery is a large flat box. It is designed to go under the passenger compartment. In theory it is possible to reassemble the cells in a different shape, but you'll need to redesign the cooling system.

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MKH
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Location: Dallas

Re: Converting BMW 2002 to electric using i3 parts

Wed Jan 09, 2019 2:19 pm

That's interesting, not seen that before. Just checked and my i3 doesn't have the manual cutoff under the charge port door
What about the cut off under the bonnet panel??
Mark H.
2015 i3 Rex, Capparis White, Tera World, Technology & Driving Assistant, Parking Assistant, Harman Kardon Audio System, 19 inch 427 wheels, EVoInnovate EVSE

jadnashuanh
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Location: Nashua, NH USA

Re: Converting BMW 2002 to electric using i3 parts

Wed Jan 09, 2019 6:52 pm

As I understand it, there's a pyrotechnic charge that disconnects the HV system in a crash. The manual disconnect is used during some service operations. Someone posted the service section here that shows where and how to do it. IT's not something a typical owner would need to access, but if you wanted to , say, replace the 12vdc battery, you should first disconnect the HV.
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV

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