1999 chevrolet venture wipersin up position when

You'll want to check the crank arm. It's under a plastic cover on top of the wiper motor and connects to the wiper linkage. When it fails the wipers park in the up position. There is a tab sticking up from the frame that it needs to hit. Make sure this isn't bent. When the crank arm is replaced it needs to be correctly timed. There must be a 4-8mm gap between the tab and crank arm at the innerwipe position.