The single wire temp sensor is the sender for the dash gauge only..it has nothing to do with the fan circuits.

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the blu , 2 wire sensor is for high fan circuit cut-in @ 105C.
You said you have replaced that sensor???


I would suggest you also do this simple test.
On the drier , there are two sensors . One with spade connectors and the other with a 6" wire pigtail.
The pigtail one is for Low fan circuit, so to be sure we are on the same page, you want to slide the wire covers back on the end of the pigtail and jumper those two wires with key ON and see if you have LOW Fan..
Compare that speed to what you see as High fan so we are sure we are diagnosing the correct circuit..
The FANS have two different circuits..a HIGH speed circuit that is triggered by the engine coolant temp sensor [ 2 wire/blu] and LOW fan that is triggered by the a/c systems high side pressure sw at the drier [ pigtail wire sensor] These are completely different circuits , even though they use the same fan motors...