Heater Coolant Control Valve for 2004-2009 Toyota Prius 1.5L L4 16670-21010

Heater Coolant Control Valve for Toyota Prius

This heater coolant control valve directs the flow of engine coolant through the cabin heater core, replacing OEM part number 16670-21010 on compatible 2004-2009 Toyota Prius 1.5L L4 models.

Overview

This heater coolant control valve is a direct-fit replacement for the factory coolant flow valve on 2004-2009 Toyota Prius 1.5L L4 vehicles. The valve opens and closes coolant flow to the heater core, restoring proper cabin heat and stable engine temperature control. It is built for Prius owners and independent mechanics handling routine cooling system repair.

Built For Performance

• Direct replacement for OEM part number 16670-21010
• Controls coolant circulation to the heater core for consistent cabin heat
• Sealed valve body designed to resist coolant leaks under pressure and heat cycling
• Constructed from coolant-resistant materials for long service life
• Fits the 1.5L L4 engine configuration used in second-generation Prius models

Fits These Machines

• for Toyota Prius 2004 1.5L L4
• for Toyota Prius 2005 1.5L L4
• for Toyota Prius 2006 1.5L L4
• for Toyota Prius 2007 1.5L L4
• for Toyota Prius 2008 1.5L L4
• for Toyota Prius 2009 1.5L L4

On-The-Job Use

• Restoring cabin heat when the original valve fails or sticks
• Cooling system repairs after a coolant leak is traced to the valve
• Routine replacement during heater core or thermostat service
• Fixing temperature control issues that trigger warning lights or poor defrost performance

Specs At A Glance

Good To Know

Q: How do I know if my heater coolant control valve needs replacing? A: Common signs include no cabin heat, coolant leaks near the valve, and erratic temperature readings. A stuck valve can also cause overheating or coolant loss.

Q: Is this valve a direct fit for the listed Prius models? A: It is designed to replace OEM 16670-21010 on 2004-2009 Toyota Prius 1.5L L4 vehicles. Confirm your part number and engine before ordering.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.