Here are the steps I would take to fix a keyboard that isn’t working.
1) make sure the laptop is turned on and plugged into an outlet, and also make sure there’s a light indicating it has power. With some laptops, if you plug the laptop into a PowerPoint with no battery in it, it will run from mains power but not charge the battery. If this happens, try turning off your laptop and reconnecting the charger directly to the mains receptacle without any other devices plugged into receptacles nearby – sometimes when another device is plugged in temporarily draws away energy from powering up your laptop properly.
2) Try disabling/reverting the video card when booting up again after checking above – visit Lenovo Solution.