Alternator/battery prob?

[Rob Winchell <rbw@avs.com>]

All -

Here is what happened:

Friday night, terrible rain/sleet storm in Boston, I drive about an hour in 
my (new) '91 200TQ. Park the car and leave it for about 3 hours. When I 
come out, there is _no_ power, not even dash or interior lights. Obviously 
wont start. I jump the car, and it starts right up, runs fine, no problems. 
Voltage gauge is showing just over 12V.

An hour later, back in Boston, about a block from my house I run through a 
huge puddle. Suddenly the Battery, Brake and Anti-Lock lights come on the 
dash. Also, the Voltage gauge is now showing just under 12V. I put it on 
the street and turn it off, expecting it will not start the next day.

Next day: starts right up. warning lights are still on, voltage just under 
12V. I let it run awhile, and adjust the power seats quite a bit (which I 
should not have done). Turn it off. Now it won't start again - barely turns 
the starter, makes some very bad "stop trying that" noises.

Other than "you need a new battery", I'd like to hear people's diagnoses of 
this. I'm sure I need a new battery, but also suspect there is something 
greater at work here.

Thanks,
Rob Winchell
91 200TQ
87 4000CS(non-Q)