My freezer starts, goes below 0*F, then shuts off at some point. However, it doesn't seem to turn back on without some kind of manual kick-start (opening the door, turning the knob, reset defrost). I saw another post that had a similar issue, and the Control thermostat seemed to be the cause.

My side-by-side refrigerator appears to have 2 Control thermostats. On the "Control" parts diagram, the Freezer control is #28, and the refrigerator control is #9 (2203251). Watching some repair videos, I notice most fridges only have one control thermostat that looks like this, and the unit is much smaller/simpler. Freezer control has the "off" position on the pane). I was told they are the same part. Do either (or both) of these devices turn the condenser off when the desired temperature is achieved and/or turn the condenser on when it needs to cool?

Other than controlling a different part of the Freezer/Fridge, are there any other differences in their functions?

Thanks for the post. I had replaced the defrost timer the other night and also tested the thermostats. So far, the refrig is working like normal with the new defrost timer. The freezer control which has white plastic (which the "off" setting on the front panel, part 2203252, terminals 3,4, & 6) shows "OL" on 3/4 & 3/6 when off (continuity on 4/6 when off), and continuity on 3/4 when on ("OL" on 3/6 & 4/6 when on). The refrigerator control--which has brown plastic (2203251, terminals 1, 2, & 3)--shows "OL" on 2/3 & 1/3 when on/colder, and continuity on 1/2 when on; and continuity on 2/3 when off/cold ("OL" on 1/2 & 1/3 when off/cold). However, the refrigerator temp looks normal for now. Both parts were original, so I wonder why they look slightly different.

Additional information:
Spoke too soon. Replacing the defrost timer may have jarred something in one or both thermostats to where it worked for a while. Now, there are periods where the condenser and condenser fan do not kick on. The only difference between now and before is that it appears to turn on after the defrost cycle. Now it looks like it might be the thermostat. I have 2 control thermostats, one for freezer (2203252) and one for the refrigerator (2203251). They discontinued the freezer thermostat. They say the 2203251 works for both. 2203251 shows terminals 1, 2, and 3. The 2203252 shows terminals 3 (Orange/black wire), 4 (red wire), & 6 (Orange wire). Not sure how I'd hook these wires up to the 1, 2, & 3 terminals of the 2203251 if I'm replacing it in the Freezer control spot. Any suggestions?