I have an amp hooked up to my U310BT to run a 12" subwoofer

I remember in my old car (same amp, different Deck) when i turned off the Deck, the amp turned off also. What i have noticed with the U310BT is even if you turn off the music source, the amp still stays on. Now that it is winter, i start my car and let it warm up for 10-15 mins before i leave. Is the amp going to drain my battery? i dont know if the car just idling is enough for the alternator to keep the battery charged.

Your battery should be fine.

I have an amp hooked up to my U310BT to run a 12" subwoofer

 

I remember in my old car (same amp, different Deck) when i turned off the Deck, the amp turned off also. What i have noticed with the U310BT is even if you turn off the music source, the amp still stays on. Now that it is winter, i start my car and let it warm up for 10-15 mins before i leave. Is the amp going to drain my battery? i dont know if the car just idling is enough for the alternator to keep the battery charged.

You'll be fine. The alternator can handle it.