Fiat Ducato 2.0 X290 (2019) Climate Control

[Reberg97]

Hello Guys,

I retrofitted a cruise control to my Fiat Ducato 2.0 from 2019.
To activate the cruise control, I had to reset the "self-learning functions". I did that and the cruise control now works. However, my air conditioning hasn't switched on since then.
I read that in order to re-learn the air conditioning, you have to perform a function in the air conditioning control unit. Now to my problem:
When I try to connect to the control unit with my interface (ELM327 - ELECTRONIC-FUCHS) and the prescribed yellow adapter, the following message appears after a short time: "ELM327 -> ECU connection failed".
All other control units can be controlled.
Can someone tell me what I'm doing wrong?

Thank you in advance!