Toyota plans to notify 2004-2007 Prius hybrid owners in early December of a Limited Service Campaign (LSC) to replace the hybrid electric water pump, according to dealer documents reviewed by Consumer Reports. There is a risk that air in the pump bearing could cause pump actuation to be slow, raising the coolant temperature and tripping a Check Engine light (Code: P0A93 with information code 346). This pump cools the hybrid system, not the engine.

Should the hybrid components get too hot, the Prius will enter a fail-safe mode to prevent damage, reducing power.

The work will take about 1.2 hours and be performed by Toyota dealerships at no charge. There are approximately 378,000 Prius hybrids in the United States impacted by this action.