Service menu?

Has anyone had any luck?

http://youtu.be/2v78Nj9QOoM

I've used this on my 535GT, but have not tried it on the i3. It does work on the GT.

Perhaps you can try it, to see esp if you can start the REx manually

I tried it on my REx and it works. There really isn't anything interesting in there. If I remember there were 4 menu options: TV (this is the only odd one), Navigation, Phone & BMW Connect and Gracenote.

TV menu had a bunch of settings like channel and frequency. I didn't play around with it.
Navigation had options for verifying GPS.
Phone & BMW Connect gave information on the built in 3G phone that is used for connected services.
Gracenote gave the version currently installed and an option to update it.