NHTSA Complaint #11449938 — 2016 TESLA MODEL S

The recent upgrade of the Tesla MCU UI (User Interface) firmware from V10 to V11 has significant User Experience problems creating a less safe vehicle. Standard pieces of automotive functionality have been moved off the main screen and into sub-menus. Two weeks ago, my car was forcefully or accidentally (may be my fault) updated to the V11 UI. To my dismay the window defrost button was moved from a single press on at the bottom of the touchscreen to multiple precise presses. I experienced how unsafe this is while driving in northern New Mexico on a snowy curvy mountain road after sunset departing Bandelier National Monument. The front windshield began fogging up as I reached 50 mph on the one lane 55mph speed limit road. Previously, a quick glance at the screen would be sufficient to make sure my finger was over the correct button. But now, the defroster button is hidden. I'm in the middle of a turn, my window is quickly fogging up, and I need the defroster ASAP. I didn't have time to take my eyes off the road for multiple seconds to make sure I was using the touchscreen correctly and wait for the slow UI animations to run. So, I did an unsafe, but least worst thing and stopped in the middle of the road. I enabled the defroster and continued the trip, but was shocked I needed to risk being rear ended to enable the defroster. These changes have not been thought through from a safety perspective. The goal seems to make the UI pretty, at the expense of safety. I could enable the defroster on previous vehicles without taking my eyes off the road at all, because they had physical buttons. The V10 defroster button location was simple to locate with a glance. The V11 defroster button requires multiple seconds and is now a significant safety hazard. I dislike the V11 firmware for many other reasons, but this is the most clear safety issue. Note: The defroster can be turned on via voice control, but it is not available in areas without mobile/cell service.