It sounds like your camera is malfunctioning. If you do not do what you are supposed to do when you press a specific button, you have several options:
- Solve the problem and continue using the camera "as is".
- Have the camera see a repair center. Have it fixed if they can fix it.
- Replace the camera and move on.
However, before considering those options, confirm that the behavior of the camera is really unexpected.
In the case of the & # 39; AF Mode & # 39; of Nikon, is only active when a "chipped" lens is connected and changed to "AF". If the lens has an "AF" position and is set to "Manual", or if any of the camera settings are set to "Manual Focus", the "AF Mode" button is not active.