Buy OEM Lexus Part # 8710730580 (87107-30580, 8710730570, 8710730571). HVAC Heater Core. Heater Core - Repair or Replace Your vehicle’s heater core handles hot water from your engine’s cooling system and

UNIT SUB-ASSY, HEATER RADIATOR

Heater Core - Repair or Replace
Your vehicle’s heater core handles hot water from your engine’s cooling system and transfers the heat to the cabin in the form of comforting heat from your vents. A failed heater core can leak that water—which is also called coolant or antifreeze—onto the floor on the passenger side. If your Lexus needs to have the heater core replaced, it's a job best left to a Lexus trained technician.