Kenmore elite side by side bottom of freezer is working top and fridge is not cold

There are several things to check. First, unplug unit and pull out from walland remove rear cover so you can clean the coils, condenser fan blades, and drain pan with spray soap and a hose nozzle. Wash out well and use a wet-vac to get water up. When I have a hand truck handy I would always unload the unit and take it outside and wash it all out from top to bottom with bleach and water. It's the best way to get it like new again. After it's clean you will be able to check it out without burning up the compressor.Make sure you cleaned the fan and that it works, then replace the cover. Removethe cover to the freezer coils and make sure it's not iced up. If so, you havea defrost system problem. You will need a meter to check it out. Your problemcan be either in the defrost system or the fan is bad if the coils were notblocked with dirt; more than likely it's the defrost system. If it is a normaltype it has a defrost timer which turns off the fan in freezer and thecompressor and energizes the defrost heater until the terminator t-stat turnsit off or the timer turns it off, whichever one is first. It's a verystraightforward system that is easy to work on. The electronic ones are totallydifferent, but normally when they go bad only the heater and terminator needsto be replaced. Just remove the cover to coils in freezer to access heater andterminator. Many times the timer is under the unit near the coils or near thet-stat in the refrigerator section. Let unit thoroughly defrost before workingon it. After removing the cover to coils you will see wires leading to a heaterattached to the coils. On a side-by-side the heater is a glass rod with anelement inside that you can see if it is bad; on a freezer on top model it isaluminum and wrapped around the coil that will burn apart often. There is adefrost t-stat attached by wire to one side of the heater and clipped onto thecoils. It is round and has two wires, one to the heater and one to the powerfrom defrost timer. With refrigerator unplugged turn timer until you hear itclick and stop. Have wires unplugged to defrost heater and defrost t-stat andget the plug and the wire supplying power to heater. Put meter on ohms and putone lead on wire supplying power to heater and one to plug prong and if timer isgood you will read about zero on both prongs – one to each wire supplying heater power. Then put one lead oneach side of heater and if you have no continuity you need a new heater.Replace heater and terminator together and be very careful when replacing it,especially on the freezer on top model because if you bend the wrong thing youwill break one of the delicate capillary tubes and lose all of the Freon whichwill ruin the unit. If the timer is bad you will need to replace it with onethat matches. You can test it before you take anything apart by advancing thetimer until the refrigerator turns off. Then see if the heater defrosts theunit and then brings the unit back on; if it does not then all you may need isa new timer, but the parts are cheap, so if you need to replace the heater andterminator you should replace the timer and keep the old one for an emergency.Here are the manuals: https://dl.dropboxusercontent.com/u/8010163/Whirlpool-Kenmore%20Refrigerators.zip
https://dl.dropboxusercontent.com/u/8010163/How%20to%20use%20Test%20Equipment%20Service%20Manu al.pdf
https://dl.dropboxusercontent.com/u/8010163/Whirlpool%20Side%20x%20Side%20Refrigerators%20and% 20Freezers%20Service%20Manual.pdf
If these manuals do not cover your model let me know the model number and how old it is. The newest models only have a defrost heater and a thermistor, usually, and you have to test the thermistors with a digital volt/ohm meter. When you check to see if fan is working in freezer make sure to press in door switch because when door is open some will turn off the fan, and some have a thermostat that will keep fan off until the temp goes below 20° F.