In some embodiments, the method includes measuring a first responsive voltage value for a first voltage drop between a first terminal attached to a first suspension spring of an actuator housing a voice coil motor for moving a lens assembly and a second terminal of the magnetic coil of the voice coil motor. In some embodiments, the method includes calculating a first resistance of the magnetic coil based at least in part upon the first voltage value and measuring a second responsive voltage value for a second voltage drop between the first terminal attached and the second terminal. In some embodiments, the method includes calculating a second resistance of the magnetic coil based at least in part upon the second responsive voltage value and calculating a relative temperature for the magnetic coil based at least in part upon the first resistance and the second resistance.