For Whirlpool WRF535SWHZ02, I ordered the recommended control board, AP6022400, which looks like it fits several models -- so first step, don't be freaked out if your fridge looks different from the one in the instructional video. Mine did, but the process is the same.
My fridge had a humidity control, so in addition to detaching the two rectangular wire harnesses, there was a blue and red spade shaped connection for the humidity switch that detached by pulling straight back.
The trickiest part of the job is dealing with the plastic tabs that hold the circuit board in place. The one for the narrower board was particularly tight. So take your time. It takes a little bit of firm finesse. Same for breaking the circuit board. Just gradually increase the pressure.
Once you have the boards in, I thought reprograming it would be a hassle but it was easy. Push in the refrigerator door switch, or if your fridge is like mine, both of them. You have to press the freezer down button three times while the switches are pressed in, then you're in the programing mode -- It should display P E. Then you can release the fridge switches (those white lever things that turn the light on and off) and hit the freezer down once more and it should display 0 0.
Next you just punch in the code that's on your serial number sticker. There is a line that says CODE followed by 2 numbers. In my case it was 12, so I just pushed the freezer up 1 and the fridge up 2. Once you have your code entered, hold the freezer down button until it starts flashing then shut the fridge. When I opened it, I could dial the fridge and freezer up and down to whatever settings, instead of having them both stuck at 7.
If you screwed it up, you can just restart from the beginning by holding the fridge switch and pressing freezer down 3 times.
One last note, if you are confronting this problem and haven't ordered the control board yet, I think it would be worth a shot to just do the programming reset process and see if that clears the issue.
Again, that's hold down the fridge light switch or switches and press the freezer switch three times -- tap, tap, tap. If the display goes to P E, you're in programming mode and you'll probably not have to get a new part.