Battery Replacement Question
 

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

If you have the radio code, just swap out the battery, the car will relearn the rest.

You can re-calibrate the E-gas but as JFP said it will relearn everything (except the radio code) on its own just fine.
There is something with the windows the one touch up down feature it has to be re-calibrated (I think) it should be in you owners manual.

I'm wondering IF there's a way to tell IF the radio has a code at all....other than disconnecting and reconnecting the battery ...then try turning on the radio?

I don't know if the "indi" tire & battery shop that I used, a few years ago, connected a jumper to the cig lighter or just changed out the old battery for a new one......all I do recall is that the radio worked fine afterwards without any fussing around.

there is no programming of a battery on the 986. The car's ECU will just think its 'new' and erase your adaptive memory, so when it starts up, itll start idling and learnign the temperature outside and all, no big deal.

Yep - def thinks time for a new battery and as others said very simple procedure on a 986.

That said... might throw your C-tek maintainer on another vehicle to ensure it too is not bad.

Had one couple years back make me question if I had a bad cell on a (newer) battery.

Swapped maintainers with another vehicle and problem followed maintainer.

Alas that C-tek had bitten the dust after ~12-15 years which was pretty good in my opinion.

Good luck :)