Here are the steps to perform a Hard-Reset on your Karoo:
Physical Buttons Reference:
Power off the Karoo by pressing the Button-A.
Press and hold Button-B.
Power on the Karoo and continue to hold Button-B until the bootloader menu appears
Use Button-B to toggle between the bootloader options until Recovery is selected.
Use Button-C to select 'Recovery Mode' as the boot mode and hold the Button-C and wait for a few seconds to go into the recovery mode screen.
When recovery loads, the screen will show an Exclamation point.
Press and hold Button-A, then press Button-B and release both.
You must first press Button-A down and hold, then press Button-B, then release both.
(These need not be long presses.)
You will see the below screen:
Use Button-B or Button-C, move to "Wipe data/factory reset".
Press Button-D to select. This formats the /data and /cache partitions, removing user data.
Again, use Button-B or Button-C, and move to "Yes -- delete all user data".
You will see the following screen: You will be re-directed to this screen.
Use Button-B or Button-C, move to "Reboot system now".
Press Button-D to select.
The Karoo will boot up like a new unit.
You will see the initial On-Boarding screen.
Login to your Hammerhead Account to restore your Routes and Rides.
You would have to download Offline Maps and pair your sensors again.