I went to the fuse box because bmw's are notorious for not turning things off right at times and running the battery down. I wanted a 100% switch spot to keep from ever having problems with the sleep mode stuff. The only switched wire in the connector works with the sleep relay and I don't want anything to do with the sleep relay
So I went to fuse #7 in the glove box. Some people have used pin#11 for a switched 12volt source aka what goes to the red wire on the ibus adapter. Its your choice on that. I just chose the #7 fuse in the fuse box to be safe.