[Frodo]

I’ve got an old Diehard in the Box, and, unbelievably, that sucker’s been in there since 2014. I’ve got a friend who, for a fee, allows me to winter-store the car in her garage (she heads to Florida for the season) and, while doing so, I’ve had the Ctek maintainer on the whole time. The car started fine last December when I went to move it over there, but the Ctek’s been giving me a red light and indicating virtually no charge. So I guess a battery replacement is finally in order.

After 9 years, I honestly don’t remember what I did last time, but I don’t recall worrying about maintaining power in the system while making the battery switch. I ask because I’ve done some searches and have gotten inconsistent results on the issue—mine is an ’01 S if that matters. I know the radio code and can obviously reset that without a problem. But my question is: do I risk anything else by totally disconnecting the car from power for that couple minutes it’ll take to switch from old to new?

I don’t have the cigarette lighter attachment, but if I was worried about it, with the Ctek could I just hook it up to the post in the fuse box and some door frame metal? And, if so, do I just leave it on the same Ctek setting that I keep it on to maintain the battery over the winter? TIA