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I swapped out the battery in my iphone 6 plus. I inadvertently removed the 2 screws at the top of the battery and disconnected those connections prior to removing the correct battery connections. I replaced the connections and bar across the top. I replaced the battery without incident. The phone booted right up but i have the following conditions:

  1. people can hear me during a phone call but I cant hear them, unless I place them on speaker phone.
  2. people cant see me during facetime, though i tested both cameras and they seem to work fine. I believe something got disconnected while I had the display open but I thought I would try this forum before taking the phone apart and putting it back together. Any ideas what might be disconnected still?

Sounds like it could be a tear in the front camera flex cable. Its extremely common since its very delicate and easy to damage. Disconnect the battery, then disconnect the display assembly. Clean all the connections and make sure all the cable are seated properly. If the issue persists, its an easy fix. iPhone 6 Plus Front Facing Camera and Sensor Assembly Replacement iPhone 6 Plus Front Camera and Sensor Cable