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I’m Almost sure I have A swollen battery, can this cause my screen to glitch colors (whole screen green/red lines) when I lock it then unlock there gone & it works perfect. Battery heats up fast. Won’t hold charge for long. Sometimes screen touch is not responsive I have to press hard then it works again? I had my screen & battery replaced in may 2018??
If the phone is pushing mostly on the bottom left / left hand side of the phone it probably has a swollen battery. The screen glitching can be caused by an expanded battery pushing against the screen causing it to bend, though you may need to replace the screen and battery at the same time if it still happens with a replacement battery or screen lifted up. I have linked iFixit guide and parts if needed if you plan to do it yourself: iPhone 6s Screen Replacement iPhone 6s Screen iPhone 6s Battery Replacement iPhone 6s Battery
