How to Troubleshoot & Replace Ge AP3796479 / WR17X11843 Evaporator Drip Pan

On our GE Profile fridge (PSCS5RGXCFSS) the Trough Drain Assembly (#815) had rusted and was spilling rusty water. The trough was not completely rusted-through yet, but close to failure. The root-cause problem was discovered as a zip-tie holding the mini-evaporator coils (#814) together on the left side bottom was not trimmed-off enough, and was deflecting the trough, tilting the trough away from the drain hole on the right. Some side-cutters clipping back the zip-tie fixed that issue. To prep the trough, I first coated it with Rustoleum cold galvanizing paint from Home Depot, as others had suggested. As a further measure, I caulked around the drain crimp with some bathtub caulk, and then sprayed another coat of the galv paint, and let cure two days. Unplug fridge. After shelves out, must remove tubing cowl on right wall (2 screws and grommets), allowing clearance to remove mini-evap cover along with Styrofoam insulation (3 screws). That reveals two more screws holding coil and trough in place. Loosen those screws just enough to work the trough up out of drain funnel at back right corner. Trim zip-tie(s) under coil if needed. Slide in new trough, with drain in funnel, and reverse steps to reassemble. Less frustrating than expected. 

After a lot of time searching on the web for causes, without much success, I started to disassemble the affected area. What I found was the drip pan had multiple pin holes in it and water was dripping from there before it had a chance to make it to the drain tube. Replaced pan and all is good. 

I had been ignoring the water on the bottom (wiping it up periodically), but then the frig temp was running high and I could hear that the circulating fan wasn't running. Based on other reports, I assumed the water was from the evaporator tray. Not surprisingly, the evaporator tray was rusted through in multiple places, and the fan was dead. Although it possible to buy just the fan, the evaporator cover assembly was moldy and the seals looked tired, and it wasn't that much more to buy the entire cover assembly and fan from here (along with a new tray). Very easy repair: Loosen two screws holding curved tubing cover on bottom right and remove the cover. Remove three screws (two on top, one on left side) holding evaporator cover assembly. Tilt back, pinch the sides of the fan connector, and unplug. The cover will come off. Loosen the two screws holding the evaporator and pan assembly to back of frig. Pull evaporator away, and maneuver tray out of funnel and off. Squirt some hot water into funnel and make sure the drain line isn't clogged. Reverse process to put new tray in behind evaporator and tighten screws, position cover part way on and reach over to plug in fan. Replace three screws holding cover and tighten. Slide tubing cover back on and tighten two screws. FIXED! If I hadn't stopped to clean up the rust stains on the back and bottom of the frig (some white vinegar helps), it probably would have taken about 15 minutes total. 

On our GE Profile fridge (PSCS5RGXCFSS) the Trough Drain Assembly had rusted and was spilling rusty water. I replace the Trough Drain 

Replaced the drain trough. The pan had two pin holes that leaked the water through the pan to the bottom of the inside of the refrigerator. Repair took time because I had never taken the refrigerator apart before. Also I gave everything a good cleaning since the draws and shelves had to come out. 

Changed cover / evaporator unit (could have salvaged the old one but it had a lot of black mold and not worth effort. Replaced drip pan (Note: going forward I will do preventive maintenance and replace this every 3-4 years whether it needs it or not) Took apart other parts with mold and cleaned/replaced 

Started removing everything from refrigerator and taking out every part and piece I could...then got to the cover over some coils with fins on them and noticed that they have front and condensation on them and therefore there was a drip pan under it...I could see pan was rusted but it wasn't until I figured out how to remove it that I could see it was rusted through allowing collected condensation to drip through and into bottom of refrigerator instead of run out out the spout and into the drain tube. Ordered the new drain pan from Appliance pros, received in two days later and installed...problem fixed! Oh yeah, also thoroughly cleaned the refrigerator while apart making it look good as new when done! 

Water was pooling in the bottom of refrigerator. I first pulled out the refrigerator and accessed the rear. I ran long plastic tie through the plastic drain line from the funnel to the evaporation pan and cleared a clog (assumed was deposits of rust from drain pan). I siphoned out all water with a turkey baster then used compressed air to blow out remainder from the line into the refrigerator. To replace the drip pan from below the evaporator coils inside the refrigerator side,remove bottom three drawers and shelves. Loosen screws and remove plastic cover from water line on right side. Remove plastic cover and foam from coil. Remove screws holding coil and drain pan to back of unit. Gently pull coil forward while working drain pan out from below coil. (I put several coats of Cold Galvanizing Paint on new pan and let cure for several days prior to installation.) Work new pan in place by gently pulling coil forward. Work pan drain tube into funnel. Install all screws and components removed in reverse order. Job took about 30 minutes. Old pan was rusted through around drain tube. Remainder of pan was badly rusted and close to penetration. 

Replaced heavily corroded drip pan and partially clogged drain tube. Definitely take the time to spray coat the drip pan with cold-spray galvanized coating and caulk around the crimped spout. Go easy repositioning the evaporator to remove the old tray and install the new tray otherwise your easy diy job is going to become way more complicated because of broken refrigerant line 

The troubleshooting hints suggested the temp sensor was a probable cause, so I bought two sensors. I replaced the sensor that is on the wall between the frig and freezer, but it did not solve the problem. I took apart the entire back of the frig compartment and after a lot of looking, discovered there was a second temp sensor that is tie-wrapped to the backside of the cooling coils in the frig compartment. It is easy to find by following the white wires that attach the sensor. The sensor itself was inserted into a form-fitting heat sink. I pushed the sensor out of the heat-sink, and pushed the new sensor into it and spiced the wires with some crimp lugs. The old sensor had a molded gasket that seals the wires, but the new one did not have that. I cut the gasket off the old one carefully by slicing it like a hot-dog bun, removed it, and wrapped it onto the new one's wires and it worked perfectly. I suppose you could also use silicone to seal it. After putting it all together it worked perfectly again. While you are doing all this work to disassemble the frig compartment, you probably want to replace the drain trough assembly. Mine has already rusted through once, and I had to replace it. It's a bad design if it rusts through.