Circuit Description

The EVO/Passlock Module supplies a 5.0 volt reference and a ground circuit to the Steering Handwheel Speed (HWSS) Sensor. The HWSS returns a voltage signal to the EVO/Passlock Module indicating the steering wheel rate of steer. The HWSS returns a voltage greater than 0.2 volts and no more than 4.9 volts when the steering wheel has been turned one quarter revolution (90 degrees). The EVO/Passlock Module uses the sensor signal to control a PWM current (Percentage Duty Cycle) to the Steering Assist Control Solenoid. The Steering Assist Control Solenoid in turn regulates the power steering pump output flow, thus increasing or decreasing power steering assist.