Join Date: Sep 2007
Sunroofs are designed and supplied by specialist suppliers, not the car maker.
My guess is the electrical control has a safety cut out to prevent problems should the switch stick ON.
I assume the Alfa uses the now ubiquitous one push with immediate release of the switch to fully open, or close, and a short push and hold to partially open, or close, the sunroof. You should not push and hold the button to fully open or fully close the sunroof. That is too long and triggers the range of movement calibration feature.
Auto up and down electric windows also use the same switchgear and software.
They auto calibrate as well. Push and hold is used to reset the travel limits for the sunroof and the windows after power has been disconnected, as for battery replacement or even a goat and then recharged battery.
These features are for occupant safety, primarily of children. Automakers are prohibited from fitting these auto close features unless they cannot be operated without the key present.
1991 Alfa Romeo 164L 5 spd
White on grey leather 230K km, owned from new