Oral b # 4717 repair.
It appears that the button to turn on has stopped working. Could this be bad batteries? I have continued to push the button and the unit might come on and work fine then I have to push the button several times to get it to turn off? Now it will not come on at all. Thought we would try opening it up, with your great instructions, and replace the batteries and see if it makes a difference. My unit is a little different than the one in the picture. Where do we buy the batteries? Thank you.