Chosen Solution
So I have just rebuilt a rather bashed up iPhone 5s using one of those iPhone 6 mini housings and I have a strange problem. When I test everything with the screen slightly lifted out of the chassis the touch screen works perfectly however when I clip the touch screen into the housing a couple of areas of the touch screen stop responding, in portrait mode the area around the “e” key on the pop up keyboard stops responding I get an r or w when attempting e, also the area where you swipe to power off goes unresponsive. If I leave the phone powered on and then remove the screen then the behaviour stays the same until I sleep the phone and wake it, then the screen responds as normal. I have fixed loads of phones in the past and just can’t seem to figure this out!! Do I have a dodgy screen or maybe some grounding problem when I close up the handset tightly?? Anyone got any ideas?? Thanks
Well don’t ask me how or why this worked but the solution was to remove the small metal washer and spring that was on the screw that holds in the home button flex, and also helps to secure the bottom of the LCD shield, initially i thought I’d put the component on the wrong way round but I would only sit correctly at on position I also verified on you tube that it was in the correct location. Some items I read suggest removing the spring / washer / ground tab would cause problems for the home button but it doesn’t appear to Once removed clipped the phone back together and all was fine!!
I would suspect an issue with the housing, either grounding (as you suggested) or pressure points causing touch issues. The only way to be certain would be to try the screen and logic board in a good condition 5S housing but I don’t that’s possible in this case.
