Interior rear fan not working properly

That describes a blown blower motor resister to a T. On high speed the blower resister is bypassed and the motor works, on all other speeds it goes through the resister and doesn't work because the fuse built into the resister has failed. The question then becomes, did the fuse fail because of age or did it fail because the blower motor is drawing excessive current. The common reason is a bit of both. To replace the resister board you need to remove the right rear trim panel to get to the HVAC case unit, then the resister is on top of the case secured with 2 screws. Unplug the electrical connector, remove the screws and lift it out. Reverse the process to replace it. The fuse I highlighted is the likely culprit, however it isn't replaceable as they build it into the board. The trim panel is held on with screws and push clips. Be gentle removing it, the plastic is likely to be very brittle after 16 years.

The blower resistor has been replaced and it's working fine. Thanks to 2CarPros for always being there.

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