The Toyota Prius has two water pumps. One for the gas motor and the other for the electric. They do not tell you about the second one and it is not part of the preventative. They just wait until it goes out and then you are stuck in the middle of no place. Mine went out at 90,000 miles. Just a week after I had the other one replaced with the timeing belt. It cost me $500 to get it replaced. All my idiot lights came on and I lost my air conditioning and the car started surging. So watch out and hey just get both of them replaced at once because the dealer will not tell you about it.