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Swapping the inverter controller in an OEM car

Posted: Sun Sep 27, 2020 10:05 pm
by johu
I've had some inquiries lately about doing a controller swap in a Leaf. As in swapping the inverter logic board while keeping the existing VCU and other surroundings.

Disclaimer: if you do this you will void warranty and depending on your jurisdiction the car will loose its road legality.

The only relevant hardware difference is the use of pin 42 of the wire harness. It is an enable signal (similar to the start signal) in the original Leaf but on the open inverter board it is the DC switch output! So make sure to not make it the output: remove the FET on the mainboard or cut the trace. You might also want to wire up the start signal instead. Not ideas as it's permanently enabled, but hey.

I think also some software mods will be necessary. First lets link in the inevitable guide from celeron55: http://productions.8dromeda.net/c55-lea ... tocol.html
Currently CAN throttle map only accepts positive values. That would need some form of modification like accepting negative potmin or so.

Lastly you'll need to map the 0x1DA and 0x55A messages to be produced by the inverter. Is that big endian again? I think so. Well ignoring that it'd be

Code: Select all

can tx udc 474 0 16 2
can tx speed 474 32 16 2
can tx idc 474 20 12 1
can tx lasterr 474 52 4 1 //kinda, sorta

can tx tmpm 1370 8 8 1 //well, its still centigrade now...
can tx tmphs 1370 16 8 1 //same here

Re: Swapping the inverter controller in an OEM car

Posted: Sun Sep 27, 2020 10:40 pm
by celeron55
There's probably some sdditional stuff in the 1da and 55a frames that the VCU or other things are looking for. What exactly? I'd start out by copying some static values from a canbus capture. If that doesn't work, then try to generate something fancier, based on the logs. Look out for checksums.

Re: Swapping the inverter controller in an OEM car

Posted: Mon Sep 28, 2020 7:06 pm
by JaniK
Well I have been thinking about this possibility for about 6months, lastly today about making the leaf happy with openinverter running the inverter VIA CAN. but didn't ask since I don't know how much there is to do, but now thats in the open I am interested.

I have a gen2 and I am thinking of maybe getting one motor+inverter separately and could use that for testing this before the separete motor goes to another vehicle.
But I have a lack of time issue now on my current projects, so sometime in the winter is best I can offer.