996 C2 2002 - Charge battery in situ or disconnect

[5STM5]

I haven't used the car for a few weeks, and the battery now won't turnover the engine (battery was new in March 2013). I'm about to charge it, my charger is full power until the battery is charged then goes onto maintenance charge.
Is it best to charge in situ, or disconnect first?
If it is disconnect what resets do I need to do when reconnecting?

Thanks

[Slobberchops]

Never disconnected mine.

[Hilux2400]

I always charge mine and leave it connected. When you get a new battery for these cars get the biggest one that will fit in the hole. It's not just the amp hour rating, you should also look at the CCA which is the cold cranking amps. I uprated my battery in my 996 and you need at least a CCA of 800. A battery of this size will allow the car to stand comfortably for about a week without starting problems.

[m3evo321]

Like many others I leave mine connected to a trickle charger when not using her:- always ready to go then