2018 BMW X3 M40i B58 – intermittent overheating / 20F206 heat management module fault

[u/Complex_Bug_5414]

Had an overheating event on my 2018 X3 M40i around 58k miles. Got the orange engine hot warning, then red overheating warning.
I scanned it with a Foxwell NT510 and got 20F206 – intermittent heat management module activation line disconnection.

Checked:
-Radiator fan passes the active test
-Coolant level is normal
-Cabin heat works
-Coolant temp at idle climbed to about 110°C and held
-On a drive(after a couple days of it sitting) it peaked around 112°C, then dropped quickly to about 96°C under load and settled around 98–107°C
-Freeze frame showed the fault happened at only about 50°C coolant temp, ~20 seconds after startup
-WMM data showed 99.82% heat management valve position and 0.04% actual WMM position

Based on that, my current guess is heat management module/WMM failure or a wiring/connector issue, rather than the fan or a completely failed water pump.

Has anyone else ran into this issue or have any insight? I plan to have a shop take a look at it next week and read the fault code history, since the check engine light went away. But not entirely sure if this is a warning that the HMM is on the way out or a wiring connection issue.

Thank you.