Hi Gary thanks for your help. I have removed everything from the back of the car and can't locate a relay. I have power at the wiper motor all the time on one terminal, the other terminal when the ignition is on and the other when the switch is turned on, the fourth terminal is a ground. I can't locate a wiring diagram to decipher what happens, I can presume one wire is to park the wiper when the ignition is turned off or the wiper is switched off. Looks like I will have to relent and take it to a dealer>