1990 240sx: battery dead but light is off

[niyaw]

I just got myself a 240sx, drove it from PA to NY (about 100 miles), did some city driving the next day, never used the cd player. The day after that decided to take a trip to CT, and play some tunes. 25 miles out as I was passing through a bridge toll booth (car idling) the battery died on me. So I got a jump start, drove back home (with cd player off), parked the car. Next day car won't start again.

What I am curious about however is that at no point during this time did the battery light come on. I checked and if I turn ignition into 'acc' position that light does come on, so the light itself works. I don't know much about the car but it looks like the cd player doesn't drain the battery when the car is off (it resets to 12:00 am every time I start the car). Also, I took a closer look at the battery and there's some whiteish stuff around the posts - corrosion I assume? Looks like that battery was in there for a while.

I have a battery I can rip out of another car (that's going to be junked eventually) but before I put it in I was wondering if there's anything else I should check. (alternator?)

Thanks for any pointers.

Edit: I should add that I have what must be the crappy factory speakers. No subs or anything powerful in this car.

[vancouverbc]

Definitely could be your alternator.

[180fan]

I'd give the batter terminals and posts a good cleaning. Ditto with the terminals at the alternator and also a look at the belt on the alternator. It would be a good idea to have the alternator checked, but if you were able to drive home after getting it jumped, I suspect your alternator's still ok, but the belt may have too much slack in it along with the terminals keeping juice from running to your battery.

[niyaw]

Thanks, I cleaned the terminals and it's working better.

[vancouverbc]

good job:)