my van has no power. A relatively new battery is drained, and nothing works. The van is a 2001 ford windstar there are about 100,000 miles on the van Thought the battery was drained, so we tried to hook up a fully charged battery and it drained the charged battery as well. Had the alternator replaced shortly before this problem started.
Answer:
Sounds like the alternator is either not hooked up completely ( wire unplugged) or the new alternator is bad.
Alternator Testing
Alternator Testing