Found this on iFixit -- Nice camera by the way!
I have fixed several of my cameras doing these steps - usually I had dust or sand in the lense barrel. You can also try to gently tug on the lense while trying to zoom and see if that dislodges anything.
1 - Listen for any sound that indicates the zoom motor is trying to extend the lense. If there is nothing, you may require a new zoom motor.
2 - Use compressed air or a vacuum to remove any sand or particles from inside the lense. You can also try using a piece of paper to slide around the lense.
3 - Lay camera flat on back and hold down the power and the shutter button - this initiates autofocus and if connector pins are out of place they will realign themselves
Here is a link...