Your physical wireless switch might be turned off. Check the front edge of the laptop chassis and ensure the physical switch is toggled to ON .
Because official support databases have archived legacy assets, hardware component manufacturers remain the safest alternative source for essential device drivers.
One of the most common issues after a clean install is an "Unknown Device." This is usually the Sony Firmware Extension Parser sony pcg31311l drivers
If your hard drive is intact and you have not wiped it, you can reinstall original drivers by accessing the VAIO Care tool and selecting "Reinstall applications and drivers".
When official support is gone
To ensure full functionality, you need to install the following driver categories in order. Installing them out of order can lead to conflicts, especially with chipset and storage drivers.
The dedicated VAIO community maintains comprehensive driver archives and guides: Your physical wireless switch might be turned off
The PCG-31311L came in two main hardware flavors. Installing the wrong one will fail, but won't harm the computer.