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I replaced the battery on my iPhone 6s, went fairly smooth, thought everything was ok, until I received a phone call, and could not hear anything from the internal speaker, works fine on speaker phone, Bluetooth, earphones. I skipped the screen removal part, and propped up the screen with a rubber band. The only thing i can think of is the screen did go past a 90 degree angle, and I may have damaged the flex cable. I took it apart again, this time removing the screen, checked all the connections, they all snapped back into place, no problem. Same situation, no sound on internal speaker. Any thoughts would be appreciated.
I would focus your attention to the actual flex cables, not the connectors. Propping up the screen can cause stress on the FCAM/Sensor flex as it has a sharp 90° curve to it. It may have torn slightly, severing the connections to the ear speaker. If that’s the case, you can order a replacement flex here and find the repair guide here.
