Chosen Solution
My GPS always shows “lost external power” and reboots unexpectedly. But the cable works fine for my other Garmin GPS, and I reset the device to default, Still not working. Please help, thank you！
It is possible that the mini-usb connector on the back of the Nuvi may have failed. Test the connector by gently wiggling it. If it feels loose, it is a an indicator that it may have become disconnected internally. Is the red light from loading still on when shutting down and reboot? It is a common problem to this GPS. Is it an Original charger and cable? Kind regards, Kevin
