Some will, most wont. The A/C button should, but the others you'll need to learn in the light and remember for night driving.
Usually take the car to the nearest Subaru dealer and have then fix it. They invented it, they should fix it.
The rear defroster (demister) on a Subaru Legacy is built into the window. The lines going across the back window are actually the defrosters. If the vehicle is equipped with a rear wiper, the switch for this should be located below the radio and heater controls.
The differential between the axles controls the AWD on a 1996 2.2 Subaru Legacy Wagon.
It is a small brown one and is easiest to get to by pushing it out the firewall side and reaching up from underneath. It should have 6 pins. Mine was Jideco Japanese brand, but NAPA had a replacement.
For the heater core. All cars have them.
check the fan relay, it could be stuck on, otherwise make sure the heater controls are not set to defrost, and the ac is off, either of these things will activate the auxiliary fan relay.
To replace the heater core on a 1992 Subaru Legacy, start by disconnecting the battery and draining the cooling system. Remove the dashboard and the center console to access the heater core, which is located behind the dashboard. Disconnect the heater core hoses from the engine compartment, then unbolt and remove the heater core from its housing. Install the new heater core by reversing the process, ensuring all connections are secure and the cooling system is refilled and bled of air.
To change the heater core on a 2000 Subaru Legacy, first, disconnect the battery and drain the coolant. Remove the dashboard and center console to access the heater core, then disconnect the hoses and any electrical connections. Remove the mounting bolts for the heater core and carefully pull it out. Install the new heater core by reversing the steps, ensuring all connections are secure before refilling the coolant and reassembling the dashboard.
The only bulb I can think of for an air conditioner is for the on/off indicator light. They use a special tiny tiny bulb only available through your Subaru dealer and you have to take the heater controls apart. This involves taking much of the console apart and the cables that come from the heater control tend to spring their clips loose and may cause the heater controls to stop working. If you can live with it not working that would be my advice. If you decide to change the bulb be prepared to spend at least an entire afternoon and keep the kids away if you don't want them to hear bad language.
failed Heater core
To replace the heater core in a 1999 Subaru Legacy, start by disconnecting the battery and draining the coolant. Remove the dashboard and center console to access the heater core, then disconnect the hoses and any mounting screws. Install the new heater core by reversing the disassembly process, ensuring all connections are secure. Finally, refill the coolant and check for leaks before reattaching the battery and testing the heating system.
The O2 sensor heater fuse on a 2002 Subaru Legacy is typically located in the engine compartment fuse box. To access it, open the fuse box cover and look for the fuse labeled "O2 Heater" or similar. If unsure, refer to the fuse box diagram, which is usually found on the inside of the cover for specific fuse locations.