How To Reset A GPS Before Selling It
System resets of GPS devices I know for a fact do not clear the data in the unit as I’ve owned enough Garmin GPS devices to figure that out.
What I’m going to tell you below specifically applies to Garmin devices, although it can be applied to any GPS device as the data I’ll mention is probably left behind in other brands as well.
This is what you have to do to a Garmin unit before selling one:
Clear the track log
The track log is a recorded route of roughly the last 50 to 200 miles you’ve driven. This needs to be cleared, and there is a function within the unit to clear that. After clearing, reboot the unit for it to take effect so it’s wiped from memory.
Truly clearing your Favorites (Waypoints)
Garmin GPS devices are notorious for not truly deleting Favorites when you tell it to, as it constantly makes backups internally so often it’s ridiculous. A system reset also does not delete them either.
After deleting the Favorites from the touchscreen menu, you have to plug in the device to your PC or Mac, look for the “GPX” folder and delete everything in it. You may see many backups in there, and maybe even an “Archived” folder. All of that has to go. Before deleting, copy the folder locally to your computer just in case something screws up.
In order to keep your Favorites from reloading themselves again and again into Favorites, all Favorites must be deleted from the touchscreen menu first, then plug in via USB, whack everything in the GPX folder, unplug from USB, shut down and leave turned off for at least two minutes, and then the Favorites data will truly be cleared.
Clearing the travel log data
This is user data that states how many miles you’ve driven since last reset, possibly the miles-per-gallon you were getting and also may have additional track logs showing exactly where you were driving. This data needs to be cleared.
After you’ve done all of the above, then you can perform a system reset.
What can happen when you don’t clear your GPS data properly before sale?
Anyone who receives the unit can learn quite a bit about you.
Track logs can be easily extrapolated, brought into Google Earth and it shows everywhere you drive. Your home, your place of work, your relatives, where you shop and anywhere else you go.
On top of that, whoever gets your old GPS device can figure out when you’re not home.
Favorites give away even more information as it lists named locations. “Home” also shows exactly where you live.
And of course if you sold the device on eBay, your name was probably attached to the sale. Even if you listed a PO box as your return address, that doesn’t matter because “Home” in the GPS still goes right to your house. Now the buyer of that GPS knows your full name, address, and everything else mentioned above.
For Garmin units in particular, it’s not a bad idea to seek out a West Marine and pay them to reset it properly
West Marine is an authorized Garmin dealer and many (but not all) can perform “total” Garmin GPS system resets per request. It’s not free, but it’s worth it to ensure the unit is absolutely and totally cleared.