Originally Posted by Gas_Up_Lets_Go

I always maintained that this was not a failure of component, but a failure during PDI (Pre Delivery Inspection) in that the supplying dealer did not check all the connectors to ensure they were correct. The plug assembly is more fragile and susceptible to moisture ingress than the normal connectors, and so when it isn't connected correctly, water gets in leading to overheating of the connector, and failure.
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Or you could ensure the connector assembly is correctly fitted together (a double click is the norm when pushing them together, but not always) with a little electrically safe grease around the weather surfaces during assembly, and a coating afterwards.