Your nuvi is empty becouse you formated.
Do you have backup of your nuvi?
If you have you must copy garmin folder (with remotesw,text,voice...) to SD card and with hex editor change all 0/: to 1/: and nuvi will start.
When nuvi start copy all garmin folder to nuvi internal memory and flash with original firmware.
Now you can delite folder garmin from SD card