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I was able successfully to replace the battery in my 3G iphone following the IFIXIt instructions and everythings seem to work just fine until someone call me and I can’t hear the caller’s voice but the caller can hear my voice. Did I misplace a cable connector? Thanks.
Your earpiece speaker might had gotten shifted during the battery replacement. Make sure its two contacts are touching where they are suppose to be. The earpiece speaker is located on the front screen. Here is the guide to it.
