Your pump is interfering only with the thermal diode? I doubt that (hold the flames) let me explain.
Your CPU has millions of transistors. Well I don’t know for sure but I bet the thermal diode is not really a diode but a transistor itself. To say that the pump is only interfering with this one unit seems highly unlikely as I am sure there are hundreds more of the same components on the same C.P.U, MB etc.
(To the PhD’s out there I know a transistor is an array of diode in the most basic sense, but I am trying to keep it simple).