Just bought my first TL and acura and my navi screen always says check disc even tho the disc looks fine dealer is talkin big $$$ anybody have similar issue in 04 please don't get mad for asking but maybe if anybody has a spare that would be so helpfull

 

I'd first try another disc, but if the dealer is stating it's the navigator in the trunk, check the second post:
https://acurazine.com/forums/3g-tl-audio-bluetooth-electronics-navigation-94/navigation-control-unit-failure-716502/

Read on through the posts for more information and results.