Circuit/System Description
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The power steering control module (PSCM) continuously monitors the voltage and current levels being commanded to the electric power steering (EPS) motor. The 42-volt circuit from the accessory power module (APM) supplies power to the PSCM pulse width modulated control circuit to drive the 3 phase motor. The PSCM compares the desired and actual current levels to detect malfunctions in the EPS motor, or the circuits to the motor.