Hi,
I drive a 2015 Mustang EcoBoost 6 speed manual. I had an issue once where I pressed the button to turn off the car and the engine kept running. The displays/ dash turned off, but I could still rev the engine. I pressed the button a few times and the dash and display would turn on and off as usual but the engine kept running. Eventually I had to stall the car to kill the engine. After this I could not recreate the issue, but I thought I'd post here to see if anyone else had experienced something like this.