Some iPhone users have seen their screens get vertical or horizontal lines across the screen. There are times when you drop your phone or put unusual pressure on the frame that can cause this issues. Also, people seem to have this issue after a screen repair job as well. When this happens, don’t panic and try the following steps.
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First determine if the lines on your screen are temporary or not. Do they stay on your screen as you use it going from app to app? If not then the issue may be pointing to an app. If you recently installed a new app and then the lines appeared then the app may be the issue. Also it may be a good time to check and see if there is a new OS update.
Once you’ve determined that your annoying lines aren’t temporary, there are a few DIY fixes that can be done but will require you to have tools to open up your phone. Essentially the problem is one of three things. Either the display connection to the motherboard isn’t secure, the screen is damaged, or the phone has been affected by a static charge.
Open up your phone as per your screen fix instructions and gently lift the display cables shown here. Also, disconnect the battery, reconnect the battery, and then reconnect the display connections making certain that you hear a little ‘click’ when you apply pressure to the cable connector.
If you’ve determined that your phone has screen damage, the first thing to do is see if you still have a warranty on your phone. If you have AppleCare warranty, the Apple store should replace your phone for free. They can also attempt to do a repair on the phone as well of course. Otherwise, your manufacturer’s warranty will not cover the accidental damage done to your phone. In that case you will have to pay for your repair.
If you performed your screen repair without an ESD band, there is a chance that you damaged some of the repair components (particularly the digitizer) due to static shock. You will have to repeat your repair job with a new screen and make certain that you purchase and properly use an ESD band that is grounded (clipped to a metallic desk or table or something that can be used as a ground).
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