MacBook Pro 13" Touch bar permanently blank
Your Touch Bar has failed and you need to have it serviced.


  The TouchID fingerprint sensor is working. But my touch bar has gone completely blank.


This very statement has come up a lot, even here on Ask Different. The touch bar and the fingerprint sensor are two completely different things - a very thin display and a fingerprint sensor - covered by a single pane of glass.  It’s a very common misconception to believe that the whole thing must be working because the fingerprint sensor is functional.

Think of the Touch Bar as a display, not unlike the display on an iPhone with the fingerprint sensor (i.e. iPhone 7+).  Many times the LCD would malfunction in someway, but you were still able to unlock it with the fingerprint reader.  The same thing is happening here.

You’ve done all the proper steps to diagnose it, but unfortunately, you’ve arrived at the only conclusion left - it’s dead.