Porsche 997 911tt Borg Warner VTG turbos

Does anyone know how to control these turbos? I did some research and on the stepper motor mount to the turbo.
-turbos themselves have servo motors, 12V PWM control.
-4 pin plug: A1 GND, A2 +12V SUPPLY, A3 ACTUATION, A4 POSITION
I was wondering what do I feed to actuation and position?
-turbos themselves have servo motors, 12V PWM control.
-4 pin plug: A1 GND, A2 +12V SUPPLY, A3 ACTUATION, A4 POSITION
I was wondering what do I feed to actuation and position?