Yes, only GTM ID, but this unlock code was stored on nuvi not in antena, if i have luck and find another old nuvi 760 i will try and let you know about results.

Look in avoidance settings if you have enabled automatc avoidance for traffic, if you have then your nuvi automaticly reroute.
If you disable traffic avoidance then nuvi will alert you when is something on your route.
If you dont have active route then TMC will not alert you of traffic ahead.