What happens if I keep leaving the radio on when the engine is off, and for how long can it stay before the battery dies?
When you open the driver's door the radio should shut off. Also, I have found if you turn the engine off and do not open the doors the radio will continue to play for a short time and will then shut off again. There are lights and a few other items that will shut down after a time with the switch off. Leaving a door open or rear hatch open with the switch off after a short time the inside lights will turn off. The car is designed so if the owner leaves something on it will shut it off to protect the battery.