Windshield Wiper/washer problems of the 2009 Nissan Murano

The contact owns a 2009 Nissan Murano purchased June 2008. The vehicle came equipped with rain sensitive wipers which was supposed to set itself based on the amount of rain. He stated the front windshield wipers would fail intermittently and would stop. He also stated in light rains, the wipers would operate as if there were heavy rains. The vehicle was taken to the dealer three times and the failure could not be duplicated. The failure and current mileages were under 20,000. The VIN was not available.