When you leave the key in the ignition in the off position does it drain or draw on the battery
Why do you ask ? Also why would you leave the keys in the vehicle ? Some of the push button ignitions might turn on power if left in the vehicle but it probably varies by vehicle . Just take them out and put on console .
Just take your keys out of the car. That’s how cars get stolen whether it is in the garage or not.
When our vehicles are parked in our attached garage, I leave the keys in the ignition turned to the “off” position. One of my previous vehicles was a 2006 Chevrolet Uplander, which is essentially the same car as your 2005: Buick Terazza.
An old mechanic I worked for as a teenager maintaining the grounds around his shop, always left the keys in the ignition. He said you could get the vehicles out quickly in case of a fire. He did have a fire that burned down his shop, but he managed to get his vehicles out in time.
There was a house fire a couple of years ago about a half mile from our house. The fire started in the garsge, but the home owner couldn’t get his vehicles out in time. The cause of the fire was a florescent light ballast in a ceiling light in the garage that set fire to the ceiling and spread into the attic. The fire department did get the cars out before the gas tanks ignited, but the cars were ruined. The family was out of the house for a year.
My house is much more valuable than my vehicles. In the event of a fire, I would like to quickly get the cars away the house.
I remember that in some Volkswagens, inserting the key would energize the accessory position. But this is not the case for your vehicle.