Had a real experience today trying to locate a problem with washer motor not working. Turned out the installer of hands free phone kit had shorted the relay when picking up the power source under dash board, had power at switch stalk, pump motor (hard to get at) but no squirt!!! only took 2 hours to track down and 1 min to beat him up. The electrical circuits in these cars take a degree of patience and ex-stream understanding of modern electronics.