Error P1110 bypass valve (turbo)

Hello Forum I drive a Saab 9-3 I, year 04/2002, B205E, 2.0Itt, Trionic T7, about 155,000 km. Since last week, the motor control indicator light has been shining on me. The reading of the error memory resulted (in the free workshop of my trust) in the following: B205E – 2.0Itt – Trionic T7 – MT/AT error memory P1110 bypass valve (turbo). After deleting the error memory the lighting of the motor control control light came back after 2 days. I assume that the bypass valve replaces we This is probably only in the original of Saab. What does this valve have for a task and how expensive is it and can it be installed yourself? Can I check if the old valve is really broken? Thank you for your help and many greetings, the Michael Mark