Thread: Using TMC in Garmin nuvi for free

Originally Posted by keith13b

I have the same problem - Nuvi 680



I went out and bought another powercord w/ traffic antenna. Same problem. The unit itself seems to only use MSN software. Do I need to change my firmware to allow other traffic subscriptions? Also the above sequence "menu Tools, Settings, Traffic, Subscriptions" does not exist for my Nuvi 680.

The best I can do is "Tools - Navigation - Avoidances - then check the traffic box

Just stuck on how to get a TMC ID or which cable to buy exactly. Those things aren't cheap and I don't want to keep buying them using trial and error!

Any help is appreciated.


Edit: Found a GTM-10 10 digit code. It stays the same regardless which antenna I use though.

You need a GTM21 - about $40.
Plug it in.
Power GPS
turn off gps
Use garmin webupdater to ensure gtm correct firmware
power up gps again with gtm21
you should have options to add subscriptions.

PS most gtm come with a subscription.