Recently a well known independent Apple Repair Shop in CNX replaced the battery on my Ipad Pro.  Now the screen has 4 vertical black lines on the right edge of the screen.  Also the right edge appears darker when I put the device on a white screen.  I took the Ipad back to the shop and asked what happened.  The answer I got was this: "it is delicate matter and we have to investigate more, please give us two days".  I thought to myself 555..  So I played dumb and politely said "take as much time as your need".

 

I am not tech savvy but it looks moisture got inside my device during the battery change?  

 

Can anyone who is knowledgeable about Ipad's offer comments on moisture getting into Apple Devices, the indications and long term effects.

 

 

https://itoolab.com/fix/vertical-lines-on-ipad-screen/

While I am no expert on display faults I don’t think tat water damage is likely to show up with the faults you described. 
moisture can cause problems but neither the lines nor darkening suggest that to me.

Finally got an answer from this shop( I will never go there again).  It took several messages on Line and a couple of phone calls).  

 

1.  Your Ipad is old

2, The circuits are old

3.  The technician had an accident during battery removal/installation(really do not know what he meant by this?)

4.  The lines on the screen cannot be removed.  Great.  Thank you and 555.  Finding a quality repair shop is really difficult.  

 

"You can pick up the Ipad tomorrow".   The Saga of the Ipad battery replacement in CNX is now over. I got to spend 3500 Baht for a new Ipad battery and black horizontal lines on my screen.  I would call this a great deal.  

 

On that note I might as well buy a new Tablet(this time I will probably buy a Samsung).