Toyota issued a recall for the Prius at the end of 2010 because of a faulty coolant pump that caused the engine to overheat. The recall affected vehicles from the 2003 through 2007 model years.
Toyota has indicated that the source of the engine's overheating problem is a design problem with the electric water pump. Due to this faulty design, the pump allowed air bubbles to pass through the cooling system, which resulted in poor circulation. The lack of circulation subsequently caused water temperatures within the engine's system to rise beyond acceptable levels.
The Toyota Prius has a built-in warning system that will activate once the engine begins to overheat. The dashboard will illuminate a warning light, and the car will shut off the power to the engine if this warning is ignored by the driver.
It's estimated that more than 650,000 Prius vehicles manufactured between 2003 and 2007 are affected by this issue. Prius owners can take their vehicle to their local dealership to receive a replacement water pump free of charge.
