possible failure of defrost mechanism causing ice to build up behind back of freezer preventing air flow into freezer and fridge. Try turning it off for enough time for ice to melt if cause.
if this is issue the repair man will need the ice half melted to be able to test the thermistor that senses the ice buildup.
Usually it takes too much labor to fix that line, Kitchenaid built in refrigerators have capillary tube which licks at the back by suction line tube. Refrigerator will need ti be moved out from cabinet in most cases. Tech would want to give You a warranty, so they usually would replace the whole sealed system for big money, but most likely it last 10-15 years. If They will fix one pipe, next year You might call him back, leak might be in different pipe, but it will be the same expensive (due to labor). Check my video out. A Year ago found leak at evaporator, explained to customer better to do the whole system, but he wanted only evaporator replaced since its so obvious. Now we will replace the whole system, Evap is ok, heater too, but now, capillary tube + suction line + drain pan heater loop(freon pipe). If You watch video thru till the end, you will see where heater on old evaporator touching evaporator coil in multiple bents.
This video I made how to change evaporator on Thermador refrigerator, which is just copy of of Build in Kitchenaid. Problem was that it was running, but ice cream never got frozen. I checked pressures, was low on freon. I checked evaporator coils - found out that defrost heater got deformed and was touching evaporator coils - so it burned holes, where freon started to leak.( I think it designed not best way). Defrost heater on this fridges way to close to evaporator coils. Check this video to get an idea what Im talking about. I hope That helps u to understand why this repair is so expensive and what causing it.
First check to make sure the water valve from th water supply is on (usually under your sink), Second, hold the water despenser switch ON. You should hear a "Hum" sound, that's the Electric water valve in the "open" position. The air will have to be purged through the water line, Filter, And the water collection tank inside the frig. The water tank keeps about agallon of water Cold for the water despenser, and will supply cold water to the ice maker, so the ice maker can freeze the cold water much faster for your ice. When holding the Water despenser, and you do NOT hear the hum sound, there is NOT power to the water selenoid. Check the connections to be ure they are tight and secure. A volt meter can also be used to check the voltage. WARNING the voltage is around 120 volts A.C., Do NOT TOUCH with bare hands!
Cleaning the dust from the condensor is what I would have done first. the second suspect is the thermostat. When they go out, they either make the refrig freeze up or just go out. the last thing would be the compressor to go out. Cleaning the condensor coil is recomended at least once a year. A good toilet brusk and "Dawn" dish soap works great! The last thing is of corse, a service call. good luck,Lloyd
From what i;m hearing, i interpret the second lowest setting to be the second lowest refrigeration/freezer setting. Which means to me, and pardon my questioning this but, it means that the machine is not being asked to do any more than it is. If you turn the dial up, would that help? It really should say "cold" and "colder" or "coldest" on or around the dial. Please let me know if this helps.. Good luck.