Check for voltages at the wiper motor connector as you try to turn the wipers on. Also check if the motor ground is good (either the motor housing is grounded or the ground is supplied through the connector). Check your wiring diagrams for the car.
If you don't have any diagrams, I can e-mail you a PDF.
EDIT: Test for voltage on the white/blk wire of the wiper motor connector as you put the wipers on FAST mode. And just for fun, hook up a jumper cable from the wiper motor body to the battery negative post and see if the wiper works (this makes sure the wiper motor has a good ground).
