Tar Heel Person>>>it has TWO heater cores,front one and a rear one.i assume the front...
8-10 hours depending on if you know what you're doing,like a shop that replaces them......
Unplug the negative battery cable, drain the coolant and disconnect the heater hoses from the core.
Detach the steering wheel. With the front tires facing straight ahead, remove the wheel side covers and screws at each side. Remove the air bag module and unplug the electrical connector, then remove the wheel nut. Place alignment marks on the wheel and main shaft.
Pull out the instrument panel after disconnecting all components on the panel. This includes the front door interior, steering column, hood lever, glove compartment, center console, clock, radio and heater controls and the audio amplifier.
Discharge and recover the air conditioner refrigerant. Remove the evaporator housing after disconnecting the refrigerant lines and electrical connector. Remove the defroster nozzle, theft deterrent, wireless door lock ECUs and the air duct.
Remove the heater housing from the chassis, the cover from the housing, then remove and replace the heater core.
Reinstall everything in reverse order of removal (heater housing, defroster nozzle, evaporator housing, instrument panel, steering wheel, heater hoses). Fill the cooling system and reconnect the battery cable.
Evacuate and charge the air conditioner. Run the Highlander's engine until it reaches normal operating temperatures. Watch the climate control operation and check for leaks in the system.
