Battery, Alternator or Other.

[Kabad]

Hi! great forum just joined yesterday. I owned a 1994 Porsche 911 that I sold last year, I was talked into buying a Boxster by my youngest daughter (I wasn't a very hard sell) and I can't believe how much I love this car, I like driving it more than the 911. I bought a 2000 Boxster with 60,000mi and have had no problems with the car until this spring.

I stored the car for the winter (I live in Minnesota) forgot to unhook the battery and this year when I tried to start it the battery was dead. I charged the battery and the car started up right away. I took it out on a 20 mile drive, my battery idiot light stayed on, I thought it was telling me that my battery was charging, not so. My radio died and then the car died. I had my wife meet me and jump start the car enough to get it home. I thought I just had a bad battery and bought a new one. But the red battery idiot lights stays on. I didn't drive it, I don't want to get caught on the roadside again.

Any suggestions? Do you think I need to replace my alternator? That's my guess, but it seems strange that it worked great last year but has a problem this year. Thanks.