I just started a new game at the mall ( the only mod I use is FreeSpawn ) and I went outside and got in a car. The HUD at the bottom was gone, ie, couldn't tell how much gas was in the car, etc. The V menu worked, somewhat. I could turn on the headlights, heater, etc. But I could not switch seats. Zombies were crowding around my car for hours, and I could not switch seats or get out of the car no matter what I did. I just was stuck there.