We've had an intermittent buzzing noise (during cooling cycles) seeming to come from the back of the freezer. Eventually, the freezer and fridge stopped cooling. I took off the back panels and fans seemed to be blowing air around fine but the condenser motor felt hot to the touch. So I vacuumed clean everything I could reach - all of the elements, coils, fans, wires, etc. I plugged the fridge in and no more buzzing. It started cooling again, and seemed to be working fine.

Fast forward one month later, the buzzing has started again during certain cycles. I found the schematics/diagnostics papers behind the kickplate and ran service tests. Everything tested well (including the fans and the freezer thermistor) except for the defrost thermostat/circuit test, which came back with a result of "shorted."

I force-defrosted everything hoping for at least a temporary fix. But when I plugged the fridge back in, the buzzing returned. It seems to be in the area behind the compressor and kicks in at the same time as the compressor fan (the fan works fine though, and continues quietly once the buzzing stops). Compressor is warm (NOT hot like last time).

Any idea what would cause a shorted (closed) result in the defrost thermostat/circuit that would also result in a buzzing near the compressor? My model is a Whirlpool GB9SHDXPS01.

Thank you for your time. - Mindy