Chosen Solution
Hey because of the stupid old battery adhesive I damaged power flex cable of an iphone se 1st gen. while trying to force remove the battery. Will the power button, volume buttons and mute button still work or should I buy a replacement? The damaged area is circeled red on image.
Yep looks like you managed to slice right into that flex unfortunately. Hard to tell just from the photo how extensive the damage is but there’s really only one way to tell if it’ll work now, and that’s to install it and turn it on! It might be annoying to remove all the components if the flex is bad and doesn’t work, however it’s probably worth the time spent if it does work and you can save some money and time on getting the replacement part.
Also test the vibration and Apple Pay. If everything works why bother?