There are two safe ways to reset your TomTom GPS in order to start over fresh without deleting your expensive maps. Tomtom.com recommends using these alternatives as opposed to formatting your GPS and deleting any updates or maps you have purchased.
Restoring Factory Settings
If you wish to completely delete all the data you've entered since you obtained the GPS, you can safely perform a factory reset. However, this should be your last resort, as all your personal data, addresses and preferences will be erased, according to TomTom's online support guide.
To restore all original settings, turn on your GPS and navigate to the main menu. Select "Change preferences," and tap "Reset factory settings."
Your GPS unit is now wiped clean of entered data, and you can start fresh when inputting new data.
Manually Resetting the GPS
Tomtom.com recommends resetting your GPS if you have difficulty turning it on. There is only one way to do this without the unit powered on, and that is by manually resetting the unit.
TomTom GPS manuals suggest using a straightened paper clip or similar object, such as the tip of a pin or a slim toothpick, to manually reset the unit. You can find the reset button on the bottom of your unit. On some units, this button is located near the SD card slot; on others, you will find it on the upper-right side of the unit. It usually reads "Reset" in tiny letters next to the button for easy identification.
If the object you choose does not fit in the reset hole, do not force it. Avoid using wooden toothpicks, as these have a tendency to shatter when compressed into small spaces.
This reset is a soft reset, which means you won't lose any data by performing this action. This is the recommended method of turning the unit on when it refuses to do so otherwise and could save you several hours of time inputting addresses.
Consider Both Options Before Erasing Memory
Weigh both methods of resetting your GPS unit before opting to restore the factory settings. In the event that you only want to restart the GPS as you would a computer, you can choose the soft reset and save yourself a lot of trouble. However, if you need to make several changes to defaults and favourites that would take too long to change manually, a hard factory reset is necessary.
Consider backing up your GPS unit prior to erasing the factory settings in case you ever want to restore it. You can do this by using the free software provided by Tomtom.com.