Yeah its a good idea using a batt to open doors but my alarm will be going spastic way before then cause it will see the voltage drop and below min voltage alarm goes off!! I think it should leave enough juice left for doors to open.

I think I would prob be quicker jumping through the boot in the middle of the night than getting into the garage and trying to connect a batt up to a connector in the dark when I half asleep!

It’s a good idea though but I don’t think it would work for me!