Climatronic VW Golf IV, Coolant Temperature

Hello,

I'm currently converting my manual climate control to Climatronic.
During a test, the control system behaved strangely; in Auto mode, only cold outside air comes (regardless of the temperature setting). However, if you only select the dashboard ventilation ducts, warm air immediately comes out.

With VCDS, I noticed the coolant temperature in the MWB; it's -99 °C for me.
I suspect this is the cause of the problem - but where does the CT get the coolant temperature?

Thank you for any help, austrogolf.

Good morning,

While reviewing the label file, I noticed the following entry:
010,4,Coolant temperature, -99.0 °C = Not relevant/unused (e.g., in VW Golf/Jetta (1J))

It seems that the MWB (presumably a technical specification) is not the decisive factor; therefore, it appears that my StG (presumably a system or component) has a malfunction!

However, I am still grateful for any tips.

Have a nice day, Austrogolf.