Defrost Issues With Whirlpool ET14JKXFN02

[MayTagRepairMan]

Model Number:
Brand: Brand
Age: Less than 1 year

I've been having defrost issues with my Whirlpool refrigerator, and I am at my wits end! What is happening is that it does not enter the defrost cycle on its own; rather, I have to manually turn the timer with a screwdriver to get it to defrost. I have replaced the following items: Defrost timer (twice), defrost thermostat and regular thermostat for refrigerated section. Once I manually initiate a defrost, the heater does come on and melt and ice in the freezer, and after about 20 minutes the timer switches back to cooling cycle, but does not automatically go back into defrost roughly 8 hours later (its rated time). This refrigerator does not seem to have any sort of defrost control board, as I looked over the parts diagram for this unit. I really don't know what else could be causing this issue. All replaced parts were OEM and correct to this Whirlpool refrigerator, and I did test them via recommendations elsewhere online. Please, if anyone has anything that could help me try and solve this I would greatly appreciate it. Thanks so much!

[MayTagRepairMan]

Update: After some more testing, I found something interesting. When running normally out of defrost cycle, Pin 2 ALWAYS has 120V across it, which is ONLY supposed to have a drop across it in the defrost cycle. Pin 1, on the other hand, does NOT have 120V across it outside of the defrost cycle, and should until it enters the defrost cycle. There is some sort of mix-up somewhere in the wiring, so could it be the wiring harness in the freezer itself? I need to find a schematic for this refrigerator, but this whole issue is just so bizarre and confusing...

[MayTagRepairMan]

Ok, so I did some more testing last night and checked the timer this morning. I made a mark on the defrost timer last night to see if it had advanced, and after checking this morning it had moved quite a bit. I took some measurements in voltage at pins on the timer, and came up with test values (all referenced to ground):

Pin 1: 120V

Pin 2: 0V out of defrost mode; when in defrost it is 120V

Pin 3: 120V

Pin 4: 120V

All are as to be expected. However, I checked the timer for advancement a few moments ago, and it has not seemed to have moved since checking it this morning. I checked the above pins again, and came up with the same results. So, the timer only advances when the defrost thermostat is closed from my understanding. However, when I check for a drop across pins 2 and 3, I get a value of 120V, which would indicate that the defrost thermostat is closed, correct? If so, then is there any reason why the defrost timer has stopped advancing? The compressor has been running, so it should definitely be moving.