Have a GE Frige # TBX18SAXPLWW. Large amounts of water collect on inside, bottom of frige. Back wall wet from frige/freezer temp control locate at upper most rear wall of unit. What could problem be?

the drain tube from the freezer to the lower compressor area is plugged with ice or debris,and when it defrosts the water in the drip pan behind the evaporator back cover inside the freezer thaws and cant drain down and overflows down thru the damper vent door to the refrigerator,remove the rear panel inside the freezer shut off unit and let thaw,then take a wire and work it down this drain hole till water comes out at the bottom of this drain tube located in the rear

its the main board relays on the board on the back panel or just inside the lower area on the left wall near the compressor compartment

Defrost the frige by unplugging it and let itsit for 6 hours open. remove the icemaker and rear panel inside freezer. drain is in the middle below coils. Look on the back of frige for the drain hose to help you locate the drain. It is hard to spot covered with ice but it is a hole about the size if a dime. Pour hot water thru the drain. It should drain down the tube to the bottom drain pan...

Have no idea who may have responded to any of your previous posts.
The defrost heater is located behind the back wall of the freezer compartment. You will have to unload the freezer and remove the icemaker to get to it. It is located at the very bottom of the cooling coils (which are officially known as the evaporator). When you remove the back wall to reveal the evaporator, in a normally operating refrigerator, you would see a light even coating of frost if the refrigerator has been running for at least 20 minutes or more.

there is a drain in the freezer than gets pluged, unplug frige from wall, put food in ice chest take hair dryer and melt ice thats at back wall in freezer remove icemaker if there, and back wall of freezer inside, melt any remaining ice, **** up water with wet vac or sponge,see the pinky size hole in the pan under the coils, point hair dryer at it for a wile. now take the the lower back cover off behind frige and blow all the dust out and find the plastic tube, about the size of your finger and put the wet vac on it until you can hear it sucking in the freezer, take e cup of hot soapy water ond poor it in the freezer pan. put everthing back and your good to go

In your shuffling of the refrigerator you may have knocked the condensate drain away from the pain near the compressor that evaporates the water back into the air inside your home. Or you may have the refrigerator leaning in a way that the water pools up near the condensate drain pipe beginning in the rear of the freezer and has frozen over and causing the water to drain over the condensate collector pan behind the rear wall of the freezer. I have more, Sea Breeze

If the evaporator coils behind the back panel of the freezer are icing up because of auto defrost failure that will stop the circulation of cold air and eventually affect the freezer too.

check defrost timer, defrost heater, defrost thermostat. In most newer models the timer has been replaced by an electronic control board. If the heater and thermostat are ok it’ll be the control.

the line that gives water to the ice maker, every time the water comes down it lives a drip of water that turns to ice blocking the line, get some hot water and a towel and place the hot wet towel on top of the line intel it melts the ice in side the line. it happens to my frige at list once a year. if that is not the problem the valve that supplies water tho the ice maker needs replacing, it's behind the frige at the bottom, where the line coming from the house meets the frige.

Defrost heater is open behind back wall. order new heater #wr55x10101 remove 4 screws 2 bottom, 2 top behind light shield, defrost freezer so ice is off of evap, replace heater with new one.

I need to make sure that your refrigerator model and make numbers are listed correctly. Im having trouble with the information listed above your comments. I have GE data base and want you to look at the hyper link listed below.  and let me know if this or I can help lead you in the correct direction, Thanks, Sea Breeze
http://www.appliance-parts-warehouse.com/general-electric-parts/General-Electric-Refrigerator-Parts-Page-6901.cfm