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I have an iPhone 6 Plus and can’t seem to get the loud speaker to work. I have nearly replaced everything on it except the logic board and I think the camera, just about everything else has been replaced including the case. Both camera’s work, the earpiece works, the headphones work, proximity sensor works, lightning adapter works, syncing to the computer works. It’ wont let me video facetime, but can audio facetime and switch to video, but no audio out of the loud speaker, only the earpiece or headphones. When I try to turn the volume up or down, the ringer display shows, but does not show the volume bar. If the headphones are in, or it is on silent, it works as it should. Any ideas? EDIT: Also, restoring it as new didn’t work either.
What happened to the iPhone prior to this; was it repaired, dropped or came into contact with water? Or did this happen out of the blue? Trying multiple replacement parts is the proper thing to do. When all of them fail to solve the problem, you are left with a logic board issue. The caveat, of course, is whether or not you know if those replacement parts are working. Unfortunately, small parts such as flexes tend to have high failure rates. If you are confident that the parts are good, then you should have your board looked at by a micro-soldering tech to see if they can identify the problem.
