GM-GMC: GMC Safari battery drained completely dead within minutes, strong smell of plastic burning, blower motor resistor, gmc safari

Question
A 2003 GMC Safari van battery went completely dead one night.  I replaced it and a few weeks later new battery was drained completely dead within 15 minutes. I had ran to the bank, parked, came back out and tried to start the van but it was dead. Key-fob, door locks, horn, clock display, not a thing worked.  There's a smell of burnt plastic also.  Something is pulling the battery down very quickly.  I had noticed that sometime the blower will not turn on with the switch and later it will start working again. Sometimes the lights in the dash will dim but its random.  Put in a new battery and it seemed okay for 3 to 4 weeks and then today I drove to the bank only to find the battery completely dead again and I was only there 15 minutes.

Answer
There are two good posiblities.  One is that you have a wiring problem.  You should see if you can locate the source of your burning smell.  The best thing for this may be your nose.  Sniff around and see if it can lead you to where the burnt wiring is.  This may require removing some trim panels or your radio or your fan motor.  The second possiblity is that your alternator is simply not charging, resulting in a drained battery in a short period of time.  Given the buring smell I would lean more towards the first than the second.  Check the connector for the blower motor resistor which is under the hood on the passenger side and has a number of wires go in and two coming out that plug into the fan motor.
Hope this helps