Fits PriusHybrid Inverter Coolant Pump - Repair or ReplaceYour hybrid vehicle has a pump that circulates coolant to prevent the inverter and other components from overheating. If this pump fails, you will likely notice few symptoms beyond a check engine light and perhaps a coolant leak. If you have reason to suspect a fault in your inverter coolant pump in your 2004 Toyota Prius, let our certified Toyota technicians inspect it at your earliest convenience.