yes, they should go back and forth. Your vacuum motor may be gummed up, and/or all dried out. Make sure you have good vacuum lines going to it with no leaks, pull the motor apart and clean and lube everything, and put it back together (make sure there are no vacuum leaks). When you turn it on, you are not getting enough vacuum to move the wipers all the way up and then back down so, they stall. ONce you turn the switch back off, it pulls it back into "park" and returns the wipers to the "park" or "home" position.
