I have a 1979 chevy malibu classic. I recently bought a new wiper motor and washer pump, hooked it all up and the pump works great, but when motor is plugged in it doesnt run with the switch. ran leads from the plug end with the wires to the motor and it works with leads when the purple wire (bottom) park position wire. and the grey (top) does the wipers low and high speed. if that is right. but when the leads are taken off and hooked up the same way it doesnt work at all. really frustrating and i don't know what could be causing it. connections seem fine. please help.