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Electric Conversion of a Modern Car

4748 Views 22 Replies 16 Participants Last post by  remy_martian
Been finding it difficult to find any examples where a modern car which was new in 2020 or thereabouts was converted to electric. All conversions happily talk about converting old cars, just with modern cars there are so many electrical modules, sensors etc, if I rip out the engine the ECU etc will light up like a Christmas tree let alone electronic systems not working rendering the car just mechanically useable bar basic electrics. Would be great to see examples. If your wondering why you'd convert a nearly new car its because currently electric cars are so expensive would it make sense to do a DIY conversion on a nearly new car? Lots of questions but no answers...help!
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I have no real answers for you but I know exactly what you mean one of the latest cars I've found with any real detail is an rx8
converting a modern car is not it seems impossible but doing it properly with everything working and not having a dash full of warning lights is somewhat more problematic
I'm doing a leaf conversion on a 2002 Mini Cooper S with 2 Bmw g30 battery packs and all the CAN bus stuff is doing my head in 馃樀 and it's relatively simple compared to the sort of cars you appear to be talking about.
 

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Exactly my point. Definately a challenge for any car onversion company out there. Try converting my VW Passat Estate 2020 SEL diesel into electric.... not a classic car with only lights/indicators, heater motor, wiper motor and radio, that's the easy conversions. I'm sure my car is loaded with tons of black boxes everywhere and complicated coding, with the slightest touch it'll all mess up and throw loads of warning lights.
 

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If your wondering why you'd convert a nearly new car its because currently electric cars are so expensive would it make sense to do a DIY conversion on a nearly new car?
You should look at the cost of the basic components, including the battery. It's unlikely you can make your own EV significantly cheaper than a factory made BEV, especially used one. Perhaps in the UK it's different, but in the US before the pandemic you could find Fiat 500e for $4000-5000, likewise with older Leafs. Plenty of newer Leafs were going under $10,000. For comparison, I recently bought a new AC23 motor with a Curtis controller from a distributor, it was about $3,000.
 

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If your wondering why you'd convert a nearly new car its because currently electric cars are so expensive would it make sense to do a DIY conversion on a nearly new car?
I agree with cricketo.
If you use new EV components the cost will be as much as buying a new production EV, because you cannot possibly buy components for as little as a manufacturer, and you cannot build as efficiently as them.
If you use salvaged EV components to reduce component cost, you might as well buy a used production EV and get a better vehicle.

I think that conversions are hobby projects for enjoyment or education, or ways to create a vehicle of type which is not currently commercial available (and it probably has to be all of those to really make sense). For example, if you want an EV pickup truck today, you have to convert one... but wait a year, and if all you want is the EV pickup just buy one.
 

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Buying new parts plus the car will cost far more than just buying an EV from a manufacturer in the first place. That would be if you can even find OEM quality parts for sale to the public. There are many aftermarket EV parts directed towards hobbyists but it is unlikely they are anywhere are robust as what is supplied to the manufacturers. Some of these crate motor plus inverter combos make the same amount of power as an entry level EV while costing 10x the used parts. Batteries can get extremely expensive if you get top quality Li-ion new.

As for the CAN bus issue, it isn't an impossible task if you have the computer skills to solve it. Each device is only sending out a minimal range of data, but the quantity and rate will be large (that is handled by computer). A CAN bus view tool is a must, and then you would have to make an substitute for the device you are trying to replace. You could also fake the sensors connected to the device to replicate the actual sensors, then let the device act as if it was normal. There are some projects out there that have done it but it can be a complex extra step which could be why so many people choose to use an older car.
 

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90s and early 00s cars keep going up in value for a reason. Insurance just gave me a quote on my old Honda a full $3k higher than I paid for it 5 years ago. Not only do modern cars suck for EV conversions, they just plain suck. History will show 90s and early 00s are the most reliable and longest lasting of all automobiles ever made.
 

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Converting a car still under warranty and presumably still in working condition seems like a losing proposition to me. Using your 2020 VW Passat as an example, you could simply sell it and buy an equivalent EV with the proceeds. No, not a Tesla Model S Plaid, but a solid used EV with an acceptable range. It will be more reliable than something cobbled in your garage and you could be driving it tomorrow.

The reason you won't often see late model conversions is because the EV components are expensive regardless of how expensive or cheap the body/frame donor is. If the purpose is to gain skill or explore an interest, a $20,000 donor with a working powertrain makes less sense than a $1,800 car with a blown engine but otherwise in good shape.
 

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Been finding it difficult to find any examples where a modern car which was new in 2020 or thereabouts was converted to electric. All conversions happily talk about converting old cars, just with modern cars there are so many electrical modules, sensors etc, if I rip out the engine the ECU etc will light up like a Christmas tree let alone electronic systems not working rendering the car just mechanically useable bar basic electrics. Would be great to see examples. If your wondering why you'd convert a nearly new car its because currently electric cars are so expensive would it make sense to do a DIY conversion on a nearly new car? Lots of questions but no answers...help!
the reason many people converted their car to an EV; Because:
1-They had a classic car they loved, but engine was blew, and to replace the engine not feasible along with hard to find parts, so they converted to EV to keep their classic car drivable.
2-They willing to spend time and labor to DYI, and find as many used part (as electric motors, batteries etc. ) that way they can save lot of money.
Like myself; I had an 04 Jaguar X-Type that engine blew out, I try to fix it but it doesn鈥檛 run right, I love the body style of my Jag, so now I鈥榤 in processing of convert it to the EV. To let some body do it for me is out of the question: Because with the cost that they quoted I couldn鈥檛 afford it, and even if I do, I could buy a brand new Model S.
See, if you buy a nearly new car to convert it to an EV( I suspected that you would have some body to do it for you) is not make sense, and all that money you spend probably you can bu a brand new Tesla ModelS
 

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Been finding it difficult to find any examples where a modern car which was new in 2020 or thereabouts was converted to electric. All conversions happily talk about converting old cars, just with modern cars there are so many electrical modules, sensors etc, if I rip out the engine the ECU etc will light up like a Christmas tree let alone electronic systems not working rendering the car just mechanically useable bar basic electrics. Would be great to see examples. If your wondering why you'd convert a nearly new car its because currently electric cars are so expensive would it make sense to do a DIY conversion on a nearly new car? Lots of questions but no answers...help!
I have a 2008 B6 Passat and have recently been wondering the very same. I have electronics and computing experience and some CanBus experience but I am not in the aurtomotive trade. I figured that everything would revolve around the ECU so the biggest issue would be if you threw away the ECU you'd probably end up with a rather expensive brick that lit up the dashboard like a christmas tree ... or not at all !
My thoughts were to flip it on its head and fool the existing ECU into thinking it was dealing with an engine...sending the appropriate signals to it to think the engine was there and running. This approach also might be fraught with problems in emulating what the missing sensors might be doing. Simple things like the fuel gauge you could emulate, but getting things like airflow sensor to return the "right" value for the currently emulated "load" might be tricky.....unless that car would happily run around at speed when the emulated conditions were that the engine was at idle all the time....
 

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People do all sorts of things for all sorts of reasons. If you have a modern car you love, but wish it were electric, and you don't mind spending a crap ton of money to get it there, then go for it. You really just need to figure out the CAN messages that need to be sent and received. Not necessarily easy, but easily implemented once solved. Sniffing CAN is simple. Sending and receiving CAN is relatively simple and can be done with an Arduino/Teensy/Raspberry.
 

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This is something I've pondered for a while! How possible is it to convert a 'modern' car?

I've read several dicussions about whether to try & simulate the sensors on the engine to fool the ECU or to replace the ECU altogether - with no clear winner between the two. Both seem difficult.

I decided to go for a third option! Most critical vehicle systems will work OK without the engine actually running - ABS, SRS, EPAS, Body controls etc. This is important in case your engine stalls on the highway - you still need steering & braking to work properly.

My solution is to insert a CAN Bridge between the original ECU and the rest of the vehicle. Filter out the messages for speed, rpm, engine temperature which may be read by other systems to change their action. PAS usually provides more assistance at lower speeds. ABS only functions at higher speeds for example.

The filtered messages can be replaced with values derived from the EV controllers and injected into the bus. I've done some preliminary work on this on a 2021 Polaris General Although this is relatively simple compared to most vehicles (only one CANBUS, 3 ECU's). My 2005 Range Rover Sport has 3 CAN networks & 16 ECU's. I've reverse engineered (hacked) a lot of that too!

I think a lot of the problem is fear of the unknown, rather than it being technically difficult. It is, though, much easier to convert a stone-age vehicle & not have to worry about all the computer stuff. Reverse engineering takes time, even if you know what you're doing

I probably wouldn't embark on this if it were my first EV conversion. Even though, this is still a challenge. Luckily, I like challenges!
 

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There have been plug-in versions of older Prius cars done.

A few 3rd party collaborations done with mainstream auto manufactures. Both Smith and Azure converted a few Ford models.

One needs the full SDK for the ECUs. In the case of Azure, it uses at least one Ford ECU that can deal with the keys and body sensors, then reprogrammed to do the electronic system monitoring.

So not fooling the ECU, but using it as a vital on-board computer.

If a company planned to convert 100+ vehicles, not competing with current offerings, it is possible one could do a collaborative project with a major auto manufacturer.
 

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hi all just looking in to converting a o4 Hyundai coupe to electric and have ben ghosting the forums for a few months coming from a more mechanical than electrical back ground wouldent deleting everything and swapping to a power distribution module to handle the BCM side of things and a stand alone ecu or some sort of controller solve a lot of problems very quickly with newer cars its something people seem to do a lot when swapping engines in cars as ecu's don't like talking to the bcm much, this solution (not cheap ) would give you full accesses to control everything
 

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I agree, the current crop of PDM's are really good! That most likely takes care of the BCM side of things. Then you can either replace the dash - or delve into CANBUS to try to control it.
In practice, you still need to add some kind of display for things like cell voltages, temperatures, SOC etc. However, you can buy these pretty much ready built.
 

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What if we took everything out and rewired from scratch? Build a new system that incorporated the the Battery Management System, etc.
It's definitely an option - but it's quite a big job! Modern cars have one hell of a lot of wiring!

The bits that will make it difficult are ABS / Traction Control / ESP, Maybe power steering, maybe Air-Bags, maybe suspension control (less likely).
Most of the above are designed to be fault-tolerant and will continue to work even if the engine is not running / broken / totally missing! That's why I took the approach of leaving the ECU in place to start up the ABS Controller.
 
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