I have an aging Dell XPS 13 Ultrabook (L322X) that’s had a pretty good life so far, bar the continual gripe regarding the Track pad (kind of a known issue due to the Cypress drivers) its been a great little laptop.

I upgraded to Windows 10 a while ago and everything works pretty well, it looks like even the Track pad issues are resolved. The one thing I noticed yesterday though was that the Function (Fn) keys no longer worked for the screen brightness. They still worked fine for Audio control and flicking Wireless on/off but absolutely zip in regards to screen controls.

I ran all the updates I could (not that there’s many!) with no joy, the actual fix was really simple. Turns out the Monitor driver just needed removing / re-adding as below –

  1. Open Device Manager
  2. Under Monitors if you don’t see ‘Generic PnP Monitor’ it’s likely this that’s broken the Fn Keys. In my case I had ‘PnP Monitor (Standard)’ listed.
  3. Right Click the Monitor device that’s shown and click ‘Uninstall’
  4. Once removed click Action from the above menus and click ‘Scan for hardware changes
  5. Check under Monitor again and you should now see ‘Generic PnP Monitor’ – the brightness Fn controls will hopefully be working again!