Tilde (~) and plus-minus (±) in wrong place on keyboard

high sierrakeybindingskeyboardsystem-prefs

I'm using a MacBook Pro with a Swedish physical keyboard, but with U.S. layout defined in System Prefs. However the tilde (~) and plus-minus (±) keys seem switched. The following key combination should produce a ~:

Because the mapping in System Prefs says so:

But it results in a ± symbol.

It seems these two keys (± and ~) are switched somehow. How do I make them work as shown in System Prefs?

Best Answer

Here’s a solution that does not use any external tools.

Run this in Terminal.app:

hidutil property --set '{"UserKeyMapping":[{"HIDKeyboardModifierMappingSrc":0x700000035,"HIDKeyboardModifierMappingDst":0x700000064},{"HIDKeyboardModifierMappingSrc":0x700000064,"HIDKeyboardModifierMappingDst":0x700000035}]}'

Now try your ~ and ± keys: they should be switched around.

Problem is, this fix will only work until the next restart. To make it permanent, you have to automatically run it on system load.

You can do that in three Terminal.app commands:

cat << 'EOF' > ~/.tilde-switch && chmod +x ~/.tilde-switch
hidutil property --set '{"UserKeyMapping":[{"HIDKeyboardModifierMappingSrc":0x700000035,"HIDKeyboardModifierMappingDst":0x700000064},{"HIDKeyboardModifierMappingSrc":0x700000064,"HIDKeyboardModifierMappingDst":0x700000035}]}'
EOF

(This is all a single command.) This stores the script from above in an invisible executable file in your home directory, ~/.tilde-switch.

sudo /usr/bin/env bash -c "cat > /Library/LaunchDaemons/org.custom.tilde-switch.plist" << EOF
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
  <dict>
    <key>Label</key>
    <string>org.custom.tilde-switch</string>
    <key>Program</key>
    <string>${HOME}/.tilde-switch</string>
    <key>RunAtLoad</key>
    <true/>
    <key>KeepAlive</key>
    <false/>
  </dict>
</plist>
EOF

(This is all a single command.) This creates a system task: ‘run the file from step 1 on every startup.’

sudo launchctl load -w -- /Library/LaunchDaemons/org.custom.tilde-switch.plist

This loads (activates) the task from step 2.

Steps 2 and 3 will prompt for your password. And now, your ~ and ± keys are permanently switched.

Note 1

This appears to work not only on the MacBook's build-in internal physical keyboard, but on the external keyboards as well.

Note 2

To undo the switching script (not the three steps), here’s the reverse script:

hidutil property --set '{"UserKeyMapping":[{"HIDKeyboardModifierMappingSrc":0x700000035,"HIDKeyboardModifierMappingDst":0x700000035},{"HIDKeyboardModifierMappingSrc":0x700000064,"HIDKeyboardModifierMappingDst":0x700000064}]}'

Note 3

To undo the three steps:

sudo launchctl unload -w -- /Library/LaunchDaemons/org.custom.tilde-switch.plist; sudo rm -f -- /Library/LaunchDaemons/org.custom.tilde-switch.plist ~/.tilde-switch

Credit

This solution is inspired by this article:

http://homeowmorphism.com/articles/17/Remap-CapsLock-Backspace-Sierra

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MacOS – swap mapping of left and right shift keys

From your edits, it seems like the specific keyboard you're using is causing the problem. I don't know any way to fix that, unfortunately, but I thought I'd answer the original question anyway.

You can remap modifier keys in OS X from at least 10.4 through to 10.10.4 by changing a Property List (.plist) file. The file is located within ~/Library/Preferences/ByHost, and is named .GlobalPreferences.[a long identifier].plist, where each user's long identifier varies. (In the Terminal, you can just use Tab-completion to pick up the specific name of your file.)

Here are the steps to copy, convert, edit, and replace the .plist:

In System Preferences > Keyboard, click "Modifier Keys" and remap at least one of the buttons (e.g. Caps Lock > Control). This will ensure that the proper section exists in the .plist, and make it easier to find.
In Terminal, go to or create a directory where you'll do the work, then:
1. cp ~/Library/Preferences/ByHost/.GlobalPreferences (then press Tab to autocomplete the unique filename)
2. plutil -convert xml1 -o ./keys-xml.plist ./keys-binary.plist
Open the converted XML file. (You can use open /Applications/TextEdit.app keys-xml.plist to launch TextEdit from the Terminal.)
Locate the section in the file called "com.apple.keyboard.modifiermapping...". You should see at least one "dict" group within that section. It will actually be one entry per specific key that's been remapped, so if you remapped Control to Shift, you'd see entries remapping LeftControl to LeftShift and RightControl to RightShift.
Modify the existing entry using the table below, changing the HIDKeyboardModifierMappingSrc key value to the Source key (the physical button you'll press, and the HIDKeyboardModifierMappingDst key value to the Destination key you want (the key you want to take effect).
Copy the entire dict section (from <dict> to </dict>, including the key mappings, and paste one per key you want to remap, changing the Src and Dst for each.
Save and close the file. Then, back in Terminal:
1. plutil -convert binary1 -o ./keys-binary_new.plist keys-xml.plist
2. cp ./keys-binary_new.plist ~/Library/Preferences/ByHost/.GlobalPreferences (then Tab to autocomplete)
Log out and back in for the changes to take effect.

Here are the key values to use for each modifier key in the Src/Dst mapping:

+-----------------+-----------+
|    Key Name     | Key Value |
+-----------------+-----------+
| None            |        -1 |
| Caps Lock       |         0 |
| Shift (Left)    |         1 |
| Control (Left)  |         2 |
| Option (Left)   |         3 |
| Command (Left)  |         4 |
| Keypad 0        |         5 |
| Help            |         6 |
| Shift (Right)   |         9 |
| Control (Right) |        10 |
| Option (Right)  |        11 |
| Command (Right) |        12 |
| ~~Kernel Panic~~|      ~~16~|
+-----------------+-----------+

NB: Key Code 16 should typically not be used.

Source: Rewritten from http://hints.macworld.com/article.php?story=20060825072451882