Thanks for showing us the disassembly.

Difficult to tell why it’s failed, but couple of things to note. These are not serviceable items. The 8mm or 10mm nuts that were holding the end cap on are exposed to road salt and corrosion, so apply excessive toque and they’ll spin off. The electrical motor that drives it could have eventually failed, but if it was noisy, and you’d mentioned that before, that could be a collapsed bearing, either low refrigerant oil, which ultimately contributed and led to the seized unit. Anyway, hope you get it back up and running. Just looking at used compressors, so around £500 on EBay, and difficult to know the life it’s had, bit like turbos unless you split them down. Hate to think what BMW would charge new.

Good job

Can you please tell us if your I3 is a BEV or a REX? The BEV has the plumbing so that the compressor operates as a heat pump as well. It makes me wonder if operating it as a heat pump puts more strain on the compressor and wears it out sooner than the REX that only uses it in AC mode.

You have a torx / impact tool on your drill may just for things like so you don't break those longboats they have a tool called vise grips also it allows you to get into small spaces and grab little tight so you can put that little 132nd or 164th of an inch turn you can even tap this boats before you try to break them free you can put water on the threads before you start loosening it a little heat also works you didn't try none of that😮😅

This compressor failure mode seems to be a minority as compared to most of them... which just grind themselves to pieces, spewing debris through the entire system... including the HV battery. Would have been investing to see some detailed inspection on the actual compressor scrolls, and see what happened there. This seems to be the fastest growing major problem with the i3s, though my 2015 BEV had failed drive motor bearings... and has been sitting for 6 months in my garage... 😢

Nice try!

what a load of crud. bmw should do better.