Suddenly my Sony Vaio Laptop with WIN 8.1 model SVX13136CXS, its function keys and ctrl keys not working and also unable to punch in number 6 in the keyboard, can anyone help. No good help from Sony online.
Try pressing the 6 key at BIOS level (ie. In a text field in bios set up) to make sure it isn't somehow related to a software or driver issue within windows. I believe the Sony Vaio function keys should also function at BIOS level to trigger a restore helper so you could test them there as well. If they don't work, more than likely hardware issue. You can order replacement keyboards from Sony for some models but from experience their parts are extremely overpriced.