Locked keyboard

Hello,

The fact that lightly tapping the Mac causes it to restart makes me think that your power cord is very poorly inserted into its socket. Check it out!

If pressing a key wakes the Mac, it indicates that the keyboard is recognized, and if after waking up it is no longer recognized, then you may have blocked the keyboard due to its dry cleaning, especially if you didn't disconnect it.

I suggest you do these three things:
1- Do a NVRAM reset: https://support.apple.com/fr-fr/HT204063. Release the keys after the 4th tone

2- Then perform a safe boot: https://support.apple.com/fr-fr/HT201262. After this safe boot, if you manage to do it since you have to press the keyboard to enter, simply restart the Mac and test if the keyboard has become usable again once the Mac has booted in Snow Leopard.

3- Finally do a permissions repair:
To do this, restart the Mac in "single mode" by holding down the Command () and S keys (or cmd(⌘) and S, depending on the keyboard) until a black screen with white text appears.

When nothing moves on the screen, press the Enter ( ↩︎ ) key.
The new line that appears should now begin with :/ root#

Now type the command fsck -yf and validate this command with the Enter ( ↩︎ ) key.
- note1 : respect the case and spaces
- note2 : in single mode, the keyboard is qwerty so to make the dash character (the one before the y), it is advisable to take the one from the numeric keyboard or use the ) key to make the dash.

Wait for the result of this command (which may take a few minutes).
As long as the result of the command contains the phrase "File system was modified", restart the fsck -yf command by validating it with the Enter ( ↩︎ ) key.

Type the command reboot and validate it with the Enter ( ↩︎ ) key.

The Mac will restart normally, and I hope your keyboard will be OK once the Mac is started in Snow Leopard.

Ritchi

Hello Wassadjin, do you have the possibility to test with another USB keyboard?
Can you also test this keyboard on another USB port on the same Mac?

To perform an SMC reset, the first thing to do on an iMac (desktop computer) is:

1°) turn off the computer and unplug it.
2°) hold down the 'power' button for 15 seconds (the one to turn it on)

https://support.apple.com/fr-fr/HT201295

Hello,

"... What does left option and power mean ...":
"option" actually refers to the alt (⌥) key. Since there are two of them on your keyboard, you should choose the one on the left to perform the indicated sequence.
power corresponds to the Mac's power button.

The operation "Shift + Ctrl + left option + power" means "Shift + Ctrl + alt (⌥) + Power button" corresponds to resetting the System Management Controller (SMC) but only in the case of a Mac laptop with a non-removable battery.

The SMC manages the following according to Apple:
- The response to the power button usage
- The response to the opening and closing of a Mac laptop screen lid
- Battery management
- Thermal management
- The sudden motion sensor
- The ambient light sensor
- The keyboard backlighting
- The management of the status light
- The battery status lights
- The selection of an external video source (instead of an internal source) for some iMac screens

If there are issues with any of these functions, resetting the SMC may resolve it.
Note: This operation is completely safe.
There are three methods to reset it depending on the Mac model:
- On a desktop Mac, you need to turn it off, unplug the power cord, wait for at least 15 seconds, press the power button for at least 5 seconds. Then plug in the power cord, wait for at least 5 seconds and start the Mac

- On a removable battery Mac laptop, you need to turn it off, unplug the MagSafe adapter, remove the battery, press the power button for 5 seconds, then reinsert the battery, plug in the MagSafe adapter and start the Mac.

- On a non-removable battery Mac laptop, you need to turn it off, unplug the MagSafe adapter, then simultaneously press the 3 keys (the left ones) Shift, Ctrl, Alt (⌥) AND the power button. Keep these 3 keys and the power button pressed for at least 10 seconds and then release everything at the same time. You can then start the Mac.

Ritchi