Sony DSC P10 Power On problem.

Hi,
I've a 2 years old Sony DSC P10. When it is powered on, it brings the lense out, goes to extreme position and starts coming in again. then it wrigles and makes some in and out jerky movements. The motor and lense assembly is smooth and is not blocked. Does anyone have any idea what could be wrong? Is it that motor has gone weak? does anyone know what happens when camera is turned on? how it determines the position?