A woman who had just performed a clown show at an elementary school crashed a Toyota sedan into a utility pole on Berkeley Avenue just before noon Monday, police and a witness said. Authorities do not know what caused the crash, Westwood police Sgt. Matthew McClutchy said. But Jack "Poppi T Clown" Erbstein of Mahwah, who witnessed the accident, said the driver was reaching for a GPS unit that fell off the windshield when she veered off the road and hit the pole.