Juan,

We also had a dead battery and replaced it (because it was >3 years old). The new battery worked OK. After a few months the new one was dead also. Replaced under warranty. A few months later also dead. Then I started checking the drain current after the car was parked. Days/weeks/months (as allways after a while you stop doing that, and thats when the battery dies again of course!).
After "years" we found 4 causes:
1. Glove box light was on all the time (amazing quality bulb, why didn't they use it for the headlights?)The lid didn't close tight enough to push the switch in. A little round peice of rubber glued to the lid (opposit of the switch) fixed the problem.
2. Drivers side footlight didn't turn of always. Not repaired yet. Just took the light out. (I can find my feet in the dark too now!)
3. Lugage light didn't switch of always. I check it now before walking away.
4. One of the electrical door locks sometimes got stuck. This one was replaced.

So when you drive the car every day for a longer period, you will have no problem. If you are an acasional driver sometimes you will have a dead battery.

Good luck!

Monique & Jörg
The Netherlands.
http://www.wiegers-2.tmfweb.nl

P1800E 120K "71
P1800ES 160K "72
850 T5R+ 160+Mls/h "95