TROUBLESHOOTING / PC & MAC
F1–F12 not working or changing volume?
If F1 lowers the volume instead of lighting up in a keyboard tester, the key is doing something: the computer is treating it as a media control. Start by checking which action your keyboard sends. A webpage cannot turn a media action into an F-key event it never receives.
1. Try a focused, one-key check
- Open the Keyboard Test and click the illustrated keyboard. Check that the status says Listening.
- Press and release an ordinary letter. If it registers, the page has a working input path.
- Press one function key, then try it again while holding Fn. On some Apple keyboards the modifier is labeled with a globe.
- Compare Key Code after each attempt. F1, for example, means the browser received that physical function-key code.
Do not press every function key at once. A single-key comparison makes it easier to tell whether Fn changes the action. If an operating-system shortcut takes focus away, click the test area again before continuing.
2. Choose the Mac function-key behavior you prefer
On a Mac, open System Settings → Keyboard → Keyboard Shortcuts → Function Keys. The option to use F1, F2 and the other keys as standard function keys changes their default behavior. Fn or Globe lets you access the alternate behavior. Menu availability can depend on the keyboard and macOS version.
Official guidance: Apple: function keys on Mac
3. Check the laptop’s own Fn mode
Windows laptops do not share one universal Fn-lock shortcut. Check the Fn-lock symbol and instructions for your exact keyboard or laptop model. Do not assume Fn + Esc is correct for every device, and do not change firmware settings simply because a webpage missed one key.
After changing a documented setting, repeat the same single-key comparison. Keep a note of the original setting so you can return to it if you prefer media controls by default.
4. Decide what the result actually shows
Works with Fn: the alternate function-key action is reaching the page; this is different from a dead key. Works in another application but not here: browser focus or a reserved shortcut is a likely place to investigate. Fails consistently in several applications: compare another keyboard before asking the manufacturer for help.
Fn itself often does not appear as a separate browser key event. Its absence from the tester cannot establish a hardware fault. To test Escape here, tap it normally; holding it for 3 seconds exits capture without clearing your results.
Common questions
Why does F5 still refresh the page?
The tester blocks ordinary browser key defaults only while its keyboard area has focus. Click that area first. Browser or operating-system-reserved actions can still be outside the page’s control.
Does choosing Mac change my system keyboard settings?
No. The Windows/Mac selector changes the tester’s visual layout and labels; it does not remap your physical keyboard or change macOS settings.