This heater failed in 2017 and again in 2022. Repaired by a local appliance shop in 2017. I diagnosed the condition by removing the fill tube assembly and it was frozen. Curious enough was that the heater over the fill tube didn't have any insulation as shown in repair videos and part photos. Looks like the repair guy didn't put the insulation back on or damaged it, or something else. Probably why it failed this second time as it was working overtime without insulation.
Ordered part and was ready to install the empty fill tube was partially frozen probably from condensation so used a hair dryer to melt the ice. It was a bit of a struggle to get the unit back in the fill tube as it was a very tight fit. Connecting the electrical for the heater and ice maker was difficult even with the top freezer tray removed. Better to remove the whole freezer drawer, but mine was full of food so I didn't do that. My ice maker doesn't have tabs that slide into the back of the freezer to hold it up as you put in screws for the ice maker so three hands would be nice to install this. I used the back of one hand to hold the ice maker in position and the other two guide and screw the thing in all at an awkward position. Ice maker now works!! Hope it lasts another 5 years or so before the next thing breaks and I buy a new fridge.
Side note: A month before this the two screws for the ice maker had fallen out and the ice maker was hanging by the electric wires not making ice of course. Found one screw and this type of screw is not standard, Ace didn't have one and Samsung does not carry them so had to use a little bigger screw. I suspect the last repair guy didn't screw them all the way in and they vibrated out over time.