Chosen Solution

Hi there. So I have an iPhone 6 that recently got water damaged, and after replacing the battery and screen I got no touchscreen. The replacement screen is a known good screen (tested on other iphone 6). I was thinking about attempting a touch ic replacement but I noticed that on boot the logo flashes for a second and comes back. Why is this brief glitch happening and is it related to my no touch problem? Thx!

Because there is more liquid damage on the board than you think it is, most of it goes under the metal shields on the logic board which need to be removed using heat but requires a hot air rework station in order to do so. Consider taking the phone to a mobile phone repair shop that does board-level repairs if you want to get the phone working again.