Fixing a TI-83 with dead lines on the screen

So I have this old hand-me-down Texas Instruments TI-83 calculator, and it had vertical dead lines on the screen:



My quick fix is just to set the contrast really high up to the point that all you see is black:

Some of the lines already disappeared before I took the photo.


After a while, all of the lines are gone:



Setting back the contrast:




Good luck!