Patent ID: 8143825

Claim:
A control system, comprising: a position control module configured to apply a driving current for positioning a rotor of a motor at a first position or a second position; a power control module configured to apply a first voltage to one of a first phase and a second phase of the motor to generate a first current after the position control module applies the driving current for positioning the rotor at the first position, and a second voltage to one of the first phase and the second phase to generate a second current after the position control module applies the driving current for positioning the rotor at the second position; and a diagnostic module configured to i) determine a first period that begins when the first voltage is applied and that ends when the first current is greater than or equal to a threshold current, ii) determine a second period that begins when the second voltage is applied and that ends when the second current is greater than or equal to the threshold current, and iii) determine whether the rotor is restricted from rotating based on a difference between the first period and the second period.