OK, I get it! Your horizontal scan is shifting. So as an example
[image|2255351]
The text smears as well as any vertical line.
This is a sign of a bad T-CON connection either the ribbon cable is failing or the solder joint of the cable is. Here’s a breakdown of the connections
[image|2255354]
The pink cables are the video cables to the LCD panel which are soldered to theT-CON board.
Sadly you’ll need to replace the display assembly [guide|123893]. Sadly, the part is hard to get used. Here’s one source for a new unit
* [https://www.thebookyard.com/product.php?cPath=39_368_520&products_id=18354|15” MacBook Pro Display Assembly - Space Grey, Apple P/N 661-08030]
* [https://www.thebookyard.com/product.php?cPath=39_368_520&products_id=18356|15” MacBook Pro Display Assembly - Silver, Apple P/N 661-08031]