I am going crazy trying to figure out why the iDrive controller knob "Enter" function (pressing down on the knob) works only on SOME of the iDrive function screens. When you power on the car, and are presented to the "Accept" function, pressing down on the controller does nothing. If you wait and allow it to time out, all the up, down, left, right, and enter functions work on the main screen and I am able to go into any of the 4 categories. If I go into "Entertainment", I can use the FM radio controls and use the knob to scroll through the stations and select them by pushing down on the knob.

If I use the up-press, and am on one of the "heading menus"......I can rotate the knob to scroll through them, but cannot select them. The same behavior exists in all the other screens that have to do with the "Vehicle's Systems" instead of the Entertainment system. I can move around the screens such as the climate control, but I cannot select anything because the Button Press does nothing. It makes no sense becasue the controller uses a serial bus and how can some commands be transmitted, while others are ignored? I understand that the radio and vehicle computers are different, but why would the vehicle computer be getting the left, right, up down, and knob turns......but not the enter function?!?!@?!?

Any help diagnosing this would be greatly appreciated. This is driving me crazy!!!