This is Turtle.
first the 40 minute cycle you speak of is new to me for the longest defrost cycle time that i have ever hear of is the 31 minute every 8 hours , but most are the 25 minute every 6 hours.
now if the defrost circuit is pulling 4 amps in defrost cycle. it is running and pulling the right amps. if it is pulling 4 amps your heater is running. Your good there.
most Refrigerator these days will pull 1.5 amps to 3.5 amps and most regular refrigerator will pull between 1.5 and 2.5 amps. So your 2 amps seem just about right.
now in your other post you spoke of a loose spade connection and not a broken connection. Was this connection broken enough to say it could break the power to that section or not ? we are looking for a cause for the defrost system to stop and have not found one yet. So now your going to have to watch it and try to determine the cause of the defrost system to stop working. here is a list item or causes that would stop the defrost system from working.
Defrost time just hang up and stop running.
Malfuctioning Defrost terminator hanging up and sometime works or other times not work.
Defrost elements is defective or loose connection at the tie in at the elements for the wire to connect.
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Now what i have heard so far it is working good now but if it messes up it will not show up as a problem for 7 to 14 days and you will see it freeze up again. now this might be the best cource of action here because of tring to do all the testing to see a refrigerator running good. wait 14 days to see if it screws up again.
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Now here is what I think and really off the record here. I think the defrost timer stop on you and when you moved it it unstuck it and went back to working. If it is frose up the heater will most of the time will not be enough to do a total recovery from the start of it all froze up.
TURTLE