Speed-sensitive power steering at vehicle speeds 0-100 km/h when steering, function - GF46.50-P-2600A

MODEL 171.4, 203 with CODE (213) Speed-sensitive power steering up to Model Year 8 

MODEL 209, 211 with CODE (213) Speed-sensitive power steering 

MODEL 215, 220 

MODEL 230 up to Model Year 8 

Shown: rotary valve housing and control bush housing, models 215, 220 left wheel lock 

Fig 1: Speed-Sensitive Power Steering Function Diagram (Vehicle Speed 0-100 km/h, Left Wheel Lock)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Shown: rotary valve housing and control bush housing, models 215, 220 right wheel lock 

Fig 2: Speed-Sensitive Power Steering Function Diagram (Vehicle Speed 0-100 km/h, Right Wheel Lock)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

As the vehicle speed increases, the energization of the SPS [PML] solenoid valve (Y10) decreases continuously; this is opened by the force of the integral push spring. The regulated pressure is transmitted via the control spool (9) to the reaction balls (4), which causes the pressure acting on the v-shaped surfaces of the rotary slide (12) to rise. The force on the torsion bar (10) is thus further increased and the driver must operate the steering wheel with a higher steering moment.

The constant constriction orifice (8) reduces the regulated pressure from the SPS solenoid valve (Y10). This is then passed on as an almost depressurized backflow to the power steering pump reservoir.