Toyota 87107-04030 Unit Sub-Assy, Heater Radiator

Prior to removing the heater core assembly, always start by taking out the evaporator assembly. Your work will go faster with the coolant completely drained and saved. To take out the instrument panel and steering column, the factory says you'll need to disconnect all connected electrical wires, which can damage the instrument panel's fragile plastic parts. This job is not easy or recommended for most home workshops. Start by taking off the car's negative power wire, and make sure you know the stereo's anti-theft code if it asks for one when it turns on. Hold off on your work until the engine reaches room temperature. Then, empty the cooling system of all liquids. When working in the engine bay, cut off the heater hoses at the firewall and use the rubber seal to block the heater core outlets, so no coolant leaks happen inside. Remove everything from the center console, glove box, glove box liner, ashtray, stereo, center dash panels, and instrument panel. Plus, dismantle the instrument panel reinforcement brace. Start by removing the dash panel heater controls. After that, take out the ECM but leave the connectors plugged in to create more room under the heater housing. First, disconnect wiring connections from the heater unit's controls. After, free all bolts from over the heater unit, then slip out the middle ventilation tube. Work down to remove the lower tube next. Take out the heater core by gently removing the bolts that hold the tubes to the case, and catch any leaky coolant using towels or paper towels. When you remove the heater core, be gentle with the plastic parts to keep them from breaking. Pull the assembly just far enough that any plastic tabs can get past anything they might hit along the way. You remove the unit in the opposite order that you installed it. Wrap up by adding coolant, reconnecting the battery, starting the engine, and looking for any fluid leaks and self-running conditions.