cold air only on MIN temp seting

[Tigger300E]

I'm trying to get my ACC back in order. Today I installed a fixed climate control unit. The previous one got burned by a faulty aux pump and the ACC only blew hot air regardless of temp setting. To be sure that this doesn't happen again I unplugged the electric wire from the aux pump - I don't need it anyway.
Now the climate control behaves a little different - it blows ice cold air but only when the temperature wheel is set to the "MIN" (click) position. If I "unclick" it the ACC starts blowing luke warm, then very hot air again. It blows cold only on MIN.
could this have something to do with the inside temperature sensor? Could unplugging the aux pump have caused the sensor to switch off as well?