Maybe try the minolta autofocus forums... With some electrical knowledge, I would guess that since there was corrosion on in the batter compartment, it is also someplace else in the wirring causing current to not flow to the motor. Look at cleaning contacts on switch or switches, and for corroded connection points in the motor circuit. If you have voltage to the motor when measured with a multi-meter, then the motor is bad. If no voltage, then there is an open switch or bad wire. My guess is a bad controller board.