my radiator fan connection broke for the 3rd time

[Fenvy]

first time was revealed by phase2, that during the swap the radiator fan (twin flex-a-lite) was having problems staying on because the connection keeps on breaking

2nd time was a month ago, the connector burned to a crisp and we soldered the wires together to bypass the connection

3rd time was yesterstoday, a different connector, where the 2 fans meets the connector melted... this time I drove pretty fast on the freeway. 5k rpm on the 5th gear where the fuel cut is.

Could hitting the fuel cut be the cause of my problem for the 3rd time? how can I contribute to the prevention of this problem?