Volvo: 850 starting problem, door locks, alternator

Question
I have an 97, 850 we have had the same problem for the past three year as it gets colder. Battery runs down, clicking but will not turnover, occasionally door locks on /off as trying to start,then battery finally dies. We have replaced 3 batteries and alternator in an effort to correct, if you have any suggestions it would be greatly appreciated.

Answer
It sounds like you have an electrical short somewhere in the system.  It wouldn't take long to completely drain a new battery with a short.  I would closely examine the wiring between the battery and the alternator, and back to the starter.  Also keep an eye out for blown or melted fuses and relays under the hood, as those will help point you in the right direction.  Good luck!