Your battery shouldn't die because you only want the radio on. You have the opportunity to turn on your car for a 10 mins between movies and if the vehicle still dies they have personnel who help jump your car after the movie. I have only seen one vehicle need a jump and that was after both movies and it was a 80's wagon . If you want to avoid the possibility of a dead battery or your car has automatic headlights bring a personal radio or they loan out radios at the office just bring an ID.
Battery operated boom box radio if you have one is best, otherwise put key in acc position for car radio, restart your car between features. You want to get there at least 30 minutes prior to gates opening to get your pick of spots. Fyi if you drive a pickup truck or very large suv theyll make you park in the back row.
Battery powered radio. Save your car battery, just get your radio and sit outside on lawn chairs, eating concessions :)
Turn key to acc.and GRT there by 7:30
If you switch off the radio display and stuff like that, it should last the two movies, but as mentioned, they do have folks to come around and jump start cars. I recommend getting there for when they open, around 6, if you want a good spot.
I usually start the car for a few minutes in between movies. When my kids were younger we used to start with the tailgate of the van facing the screen then turn the car around during intermission. But if your battery does die they have dealt with it before and have jumper cables. It happens.
Hybrid. Runs off batteries until they get low and the engine turns on for a minute to charge then shuts off, repeat.
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