Thread: Enable features in your nuvi 12xx, 13xx and 14xx - JCV, LA, TTS

After entering the diagnostic mode and attaching USB cable, verify the following:
1. there should be no hard disks in "My computer" related to garmin device. If there are, you are not in pre-boot menu.
2. Start device manager: My computer->properties-> hardware->device manager. If your device is in correct mode for updating, you should see "Garmin device" attached in in list of hardware (not as mass storage!). Check that there are no problems with the driver. When doing this for the first time, windows needs some time to install proper drivers to run this hardware in this mode.

When you verify that the above is OK, run updater.exe again, click to "USB device" connection and try again. The error message you described usually appears if you use COM ports as a mode of connection in updater.exe. (auto-detect on COM ports will not work!)