I have a Samsung RS265TDRS (there is no /XAA or /XAA-1 after the model number as listed on the label inside the refrigerator).

The freezer works fine but the refrigerator is not cooling below 45 degrees. I have replaced the main control board, the evaporator fan, the thermal fuse, and the temperature sensor (the one located near the top of the fridge). None of this has fixed the problem.

The frost pattern on the evaporator coils is fine. The defroster is working. The drain pipe is occasionally clogged with ice but even when I have unclogged it the refrigerator will not cool below 45 degrees according to the temperature reading on the display panel.

Why is this happening? What else could be causing this problem? The only part I haven't replaced is the power inverter board but I don't see how that would cause a problem like this.