Valve Body Solenoid and Pressure Regulator Control
WARNING: This page does not describe the selected car, but rather 43 other vehicles, including the 2006 BMW M3, 2006 BMW 330Ci, 2006 BMW 325Ci, 2005 BMW M3, and 2005 BMW 330xi. However, it is still accessible from the selected car via links, so may be relevant.
The GS 20 activates the 3 shift solenoids by individual switched ground output control signals. The main oil pressure and torque converter lock up regulators are controlled by a Pulse Width Modulated (PWM) control to ground. PWM control modulates the hydraulic control pressures based on the current AGS shift program and maintains adaptive pressure control.