When the pump malfunctions, the car's hybrid system switches off to prevent overheating and the vehicle's regular gasoline engine takes over, said the company.
The auto giant is calling the repairs, "a customer satisfaction campaign."
Among the cars that need fixing, 390,000 are in North America and another 180,000 are in Japan. The pump problem also affects 70,000 Prius cars in Europe.
Late 2009, Toyota recalled more than 11 million vehicles globally for various problems including faulty gas pedals, floor mats that can trap accelerators, defective braking and stalling engines.
The Associated Press contributed to this report.