TOKYO (AP) - Toyota is fixing the pump that cools the hybrid system in 650,000 Prius cars - the Japanese automaker's prized green vehicle - but is adamant the repair being carried out worldwide isn't another recall.

Toyota Motor Corp. spokesman Paul Nolasco said Tuesday the coolant pump in Prius cars for model years 2004 through to 2007 is being replaced because it doesn't work properly.

But the Japanese automaker is calling the move a "customer satisfaction campaign" because the problem doesn't warrant a recall under regulations where the vehicles have been sold, according to Nolasco.

Of the Prius cars that need fixing, 390,000 are in North America and 180,000 are in Japan. The problem affects 70,000 Prius vehicles in Europe.

The problem with the Prius, which is closely associated with Toyota's reputation for innovative technology, is the latest embarrassment for the world's No. 1 automaker, which has recalled more than 11 million vehicles globally since late last year.

The massive recalls cover a wide range of models for various problems, including faulty gas pedals, floor mats that can trap accelerators, defective braking and stalling engines.

The popularity of the Prius in Japan had been one bright spot in Toyota's performance, although worries remain that its image in North America has not recovered from the recalls. The hybrid was Japan's best-selling car for the 18th straight month in October, even after green vehicle subsidies ended.

The Prius switches back and forth between a gasoline engine and an electric motor to deliver better mileage than conventional cars. The latest problem affects the core hybrid system.

Toyota said there have been no reports of accidents related to the coolant problem, but 300 problems were reported in Japan, and 28 outside of Japan. It was not immediately clear when owners were being notified to bring their cars in for repair.

Toyota is the only major automaker whose U.S. sales have been sluggish despite a recent onslaught of incentives that have boosted other automakers' results - underlining how its once sterling image continues to be tarnished in that crucial market.

Toyota faces hundreds of lawsuits in the U.S., many from families of people who died or were injured in accidents related to unintended acceleration suspected of being linked to the quality lapses.