From Factory Reset
How To Factory Reset a Garmin nuvi 310
- Start with the device OFF and unplugged from the power source.
- Use your index finger to press and hold the top right corner of the touchscreen.
- Power the device ON while continuing to press and hold your finger to the top right corner of the touchscreen.
- After the device powers ON, you will see the message: Do you really want to erase all user data?
- When this message displays, remove your finger from the top right of the touchscreen and touch Yes.
- The device will now go through the Reset.
- Follow the onscreen instructions to set up your nüvi.