Battery light on - any tips

[markk]

MY2001 BoxsterS, purchased new, 75000km year to date.

Last Saturday my second battery, put in in oktober 2006, failed all at once. Started the car, noticed a little bit slow turning of the crack but started immediatly. Didn't give much notice to it. 4 years battery getting a bit worn, and the car was standing still for 2 weeks or so.

Drove it, stopped, took some photo's. Started again. Same behavior. Bit of laggy cracking but immediat startup. Hmmm, time for new battery I though.

Drove it again for a while. Stopped again for photos. Then tried to start. When I turned the key all electrics dipped out completely from the starting. But it started, on it's last "breath". Clock was reset, radio was reset (code entrance). Driving home a few minutes later the whole Chrismas tree of light came up. First the battery light, then the airbag light, then the abs light.

At home I put the car on a charger. Tried it on Sunday. No luck. Clicking sound. Battery dead. Alarm went off. Pfff...

Today installed brand new battery. Everything is fine now. Crack's ok, start's ok, only battery light stays on. Drove it a few minutes. Power-steering is fine so I guess the belt is ok.

From searching the internet I guess my alternator, or at least the diode pack, has failed as a consequence of the sudden death of my battery.

Any ideas, tips?
- Replace complete alternator or try to fix the current one by sending it to a specialist who can fix diodes etc.
- While in there, replace belt as well ? It is still the original one, now about 75000km worn and 10 years old.


Mark.