My Pixel C tablet doesn't respond to the unlock pattern and the recommend action to debrick it doesn't work I have had this Pixel C for about 3 years, possibly more.
Two days ago it stopped responding to the unlock pattern.  This seems to be a fairly irregular thing on Google devices and never fixed.  The recommended course of action is to do a factory reset.
However when I start the device with volume down and power the only options I see are:

Restart this device

Does as expected.


Switch to fastboot mode

Goes to a screen stating &quot;Waiting for fastboot command....&quot;


Reboot in Android Recovery

Reboots and shows the dead android with &quot;No command&quot; below it.


Turn off this device

Does as expected


Switch to USB recovery

Shows a page stating &quot;For more information on USB recovery, please visit: g.co/c-recovery.  That page tells you to open up Settings - I can't unlock the device so I can't do that. If I could unlock the device I wouldn't need to do this!



The additional information is:
PRODUCT NAME: GOOGLE Smaug
HW VERSION: 5
BOOTLOADER VERSION: Google_Smaug.7900.139.0
LOCK STATE: Locked
How do I debrick my tablet?
Just in case anyone else comes this way searching for an answer, I did get one on the XDA forums.
The solution is to start the device with volume down and power pressed.  This brings you to the menu I described in my original post.
Select the Reboot in Android recovery option.  Once you get the dead android logo hold power then press and release volume up, then release power.
That will bring up another menu which allows you to do a factory reset.
Once that is done you can restore your tablet.