Modern consumer refrigerators only have coils in the freezer. In the lower back of the freezer there is a small fan and possible a damper (flap that opens/closes) to push cold air from the freezer to the refrigerator. Given that the freezer is 18 deg, it's probably cold enough to keep the fridge area at typically 34 deg. So the cooling system (compressor, coils, thermostat) are not working properly to keep the freezer at, typically 0 deg. Possible causes: partial loss of refrigerant gas, icing around evaporator coils (in freezer), compressor failing, dust clogging condenser coils (under fridge), condenser fan clogged or broken (under fridge), thermostat failure. I'd start with condenser. Remove the slotted trim at the bottom front and look in with a flashlight. Are the coils clean? Pull out the fridge and remove the lower back cover (usually cardboard). You can now see the coils and fan. Clean and blow them out. If it's icing, it probably means freezer door not closing tight. If auto-defrost not working properly it would probably get worse over the period of a few days so not likely.
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Modern consumer refrigerators only have coils in the freezer. In the lower back of the freezer there is a small fan and possible a damper (flap that opens/closes) to push cold air from the freezer to the refrigerator. Given that the freezer is 18 deg, it's probably cold enough to keep the fridge area at typically 34 deg.
So the cooling system (compressor, coils, thermostat) are not working properly to keep the freezer at, typically 0 deg. Possible causes: partial loss of refrigerant gas, icing around evaporator coils (in freezer), compressor failing, dust clogging condenser coils (under fridge), condenser fan clogged or broken (under fridge), thermostat failure.
I'd start with condenser. Remove the slotted trim at the bottom front and look in with a flashlight. Are the coils clean? Pull out the fridge and remove the lower back cover (usually cardboard). You can now see the coils and fan. Clean and blow them out.
If it's icing, it probably means freezer door not closing tight. If auto-defrost not working properly it would probably get worse over the period of a few days so not likely.