Steering Angle Sensor: Description and Operation

Handwheel Sensor - Mounted On Steering Column.:

Handwheel Sensor Wiring:

DESCRIPTION
The optional power steering system used on Saturn is a rack and pinion design. The pump in this system features an Electrical Variable Orifice (EVO) design. The major computer components of the power steering system are the EVO actuator, Vehicle Speed Sensor (VSS), and power steering pressure switch.

NOTE: A Handwheel sensor is used on the Coupe models only.

PURPOSE
Unlike conventional power assisted steering systems, the Electrical Variable Orifice (EVO) feature adjusts the amount of steering assist to the speed of the vehicle. Higher assist is provided at low speeds and less assist is provided at high speeds. The Powertrain Control Module (PCM) monitors and controls the sensors and actuators.


CIRCUIT OPERATION
The Handwheel sensor, mounted in the steering column, is a potentiometer that signals the position of the steering wheel to the PCM. The PCM uses this information for control of the electrical variable orifice (EVO) solenoid. The Handwheel sensor generates a 0 to 5 volt signal to the PCM for every 90 degrees of steering wheel rotation.