TORRANCE, CA - Toyota Motor Corp. has launched a "limited service campaign" to repair cooling pumps on about 378,000 MY 2004-2007 Toyota Prius cars sold in North America, reported. 

In the cars involved, air can leak into water pumps that cool parts of the electric drive system. When there is excess air in the cooling system, bubbles can form that inhibit cooling. 

When sensors detect overheating in the electric drive system, a warning light is triggered. In addition, the car's total driving power will be reduced. 

Dealers will replace the water pump free of charge.