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I needed to replace the battery for someone’s iPhone 7. I replaced the battery and everything worked fine except the home button. I opened up the phone again to fix it and that’s when one of the ribbon cables tore off. It was the smaller of the two (the one on the right) I tried to turn the phone back on but it won’t power on anymore. Is that cable needed to turn the phone on or did I mess up something else ? Thank you
As nearly as I can tell, the connector you’re referring to is labelled as the fingerprint sensor, which I assume also includes the home button functions. The picture below is from a vendor on AliExpress.
If that’s the one you’re referring to, it shouldn’t keep the phone from booting, although you may have difficulty navigating the phone without the use of the home button. Is the on-screen home button still a thing? If you can get to the menu to turn that on, it should let you work around the torn cable., assuming you can get the phone to power on again. Is there a chance the LCD cable was damaged as well, and perhaps you just can’t see anything because the screen isn’t working? You might try hooking it up to a computer and seeing whether iTunes recognizes it. Although you can buy replacement home buttons with the cable, unfortunately you’ll lose the fingerprint sensor function, as the home button is paired to the logic board and only Apple can do that pairing. The only other choice is to see if you can find someone who is experienced at microsoldering to replace the flex cable and keep the original sensor; not even sure if that’s possible, but outside of taking the phone to Apple for repair, that’s the only way you’re going to restore the Touch ID function. EDIT: Apparently the pairing data for the home button is kept in a single IC that can be removed and transplanted to another Touch ID assembly. You do have to have specialized equipment and experience to do that work though. There is a video guide for that repair here in iFixit if you’re curious. iPhone 7 Home Button Touch ID Hardware Repair
