A disk drive is disclosed including a disk, a head coupled to a distal end
of an actuator arm, and a voice coil motor (VCM) operable to rotate the
actuator arm about a pivot to actuate the head radially over the disk,
wherein the VCM comprises a coil. Control circuitry within the disk drive
measures a load resistance of the coil prior to executing a load
operation, wherein the load operation moves the actuator arm off a ramp
to load the head onto the disk. The load resistance of the coil is then
converted into an initial coil temperature estimate.