Avante or I35 sequential box problem

Good morning friends,

they can give me an idea of ​​a diagnosis so that when I go to the workshop I already carry ideas.

The problem I have is with the sequential box, using in automatic "D" does not give problems, but wanting to use the sequences and give it to the speed with the "+" does not rise, the "-" if it works and falls speed, but the "+" no, I will appreciate your ideas.