Circuit Operation

The MAGNASTEER system uses inputs from the ABS wheel speed sensors. The Electronic Brake Control Module/Electronic Brake Traction Control Module (EBCM/EBTCM) then determines the desired amount of power steering effort.

The EBCM/EBTCM constantly compares the amount of current flowing through the MAGNASTEER actuator to the desired current the EBCM/EBTCM has calculated. The EBCM/EBTCM can change the amount of current flowing through the MAGNASTEER actuator, which causes the pole pieces in the actuator to want to align themselves with the permanent magnet attached to the rotary input shaft. The more current flow, the stronger the magnetic field generates, which will increase the torque necessary to turn the input shaft. This will generate higher steering efforts. If the actuator is disconnected, the magnetic force generated by the actuator will be nonexistent, leading to maximum power steering effort.

The EBCM/EBTCM has the ability to detect malfunctions in the MAGNASTEER actuator and its circuitry. Any malfunction detected can cause the power steering effort to remain at a medium value for all speeds.

When the system is operating normally, increasing the vehicle speed will decrease power steering assist, allowing the driver to have improved road feel and directional stability.