Drain engine coolant from the radiator and cooling system. While working in the engine compartment at the left strut tower, detach the electrical connector at the heater valve, loosen the hose clamps, and pull the coolant hoses off the valve, using shop towels to catch any dripping coolant. Remove the heater valve from its rubber mounts. For installation, reverse the removal process, ensuring to inspect hoses and rubber mounts, replacing them as necessary, and using new hose clamps. Finally, fill and bleed the cooling system.