This may seem like a silly question, but what happens if I am parked with the TCH in "ready" mode (turned on) for a long period of time.

I was sitting in my car in Ready Mode playing around in the car, talking on the phone and the battery just kept getting lower and lower. The ICE never really kicked in to charge things.

What happens if I sit like this too long? Will the battery die? Will the ICE keep things charged?

As an example, my wife goes into a store to shop and I want to sit in the car (with the AC on) until she returns to the car. Am I hurting the car or risking a dead battery?