That error is "The T reel FG cannot be detected in PLAY or REC mode." The first thing to do is power down the deck, pull the top cover and manually unthread and remove the tape. Power the unit back up, insert a junk tape and watch the threading process. All may be well. While the top is off check the innards. Is it full of dust bunnies stuck to globs of grease? Could be time for a good servicing.
You can run a diagnostic test by pressing the Menu button and the back arrow at the same time. (Be sure you have the Character switch On and a monitor hooked to the Super output Video 2) Select Service Support, select Error Log, select Error 02-674. The rest of the menu options (Yes and Next) will test the T Reel. Good luck