Manual climate problem on W202

[ibrgles]

Hi! When I put both temperature regulators to white marks on my manual climate table in W202/220 D it happens that sistem turns to heating or cooling (deppending of season) on driver side "by his own will". When I crossower the wires on duovalve the same happens on passenger side. That means that duovalve works correctly but something is wrong somewhere else. Does anybody have a wiring diagram or knows how the climate sistem works, to help me fixing the issue? TNX!