Here is shortcut jumper ways to repair iphone 4 on/off key easly
By this way you can easly repair iphon 4 powers switch if on off flex is damaged and you don have that flex or you are unable to buy are somewhere these costly part are no available,billow picture will show the point of on/off key on motherboard,if you are technician then you can easly make jumper to repair broken on/off flex or on/off flex connector
this is power key positive point on main board for ground supply you can easly found on any corner of mother board.just check supply and make it happen.
NOTE – While this repair will fix the On/Off button, if you’re having issues with the noise buggy mic, proximity sensor esue,or ambient light sensor, so always take care while repair iphone specially if are you working on its motherboard,always use good quality disassembling tool and proper knowledge to check supply and using a hot soldering iron.
This will also helps you to turn on iphone when power key is broken,without replacing power key flex.
if your iphone power key is broken and your phones charging also not working ,this tricks will helps you alot in that case,easly short positive power point with ground and make your iphone alive again.
best of luck
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