The high fan will not trigger until the coolant temp is 105C.
The low fan will not trigger until the a/c systems high side pressure detects a high thermal load.

Are either conditions being met//

You may have a poor connector at the blu 2 wire sensor or a bad sensor.
And on the a/c low fan, you may be low on refrigerant. Check eyesight.
You may also have bad insulation wire harness.
Have an ohm meter?????????

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A Dalton