My iPhone 11 randomly powers off

Question

iPhone 11

Released September 20, Apple's mainstream 2019 iPhone comes with a 6.1" LCD touchscreen, dual cameras, and six available colors. Successor to the iPhone XR.

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Joshua P @joshuap74230

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crwdns2931729:0crwdne2931729:0: Dzi 24, 2025

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My iPhone 11 randomly powers off

I am fixing a IPhone 11 for a friend. His phone would randomly power off, and would drain the battery too quickly. I considered the best repair to replace the battery. I bought an IFixIt kit for the phone, and it replaced the OEM battery for the new one. The phone still has the same issues. Is it a circuit issue? The back glass is shattered on the top left corner before I fixed it. Would that have caused something?

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Just to clarify, does it power down completely, requiring a power button press to turn back on, or is it restarting; i.e., power down then power back up by itself?

crwdns2934271:0Dzi 24, 2025crwdnd2934271:0 Jerry Wheeler crwdne2934271:0

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Just to clarify, does it power down completely, requiring a power button press to turn back on, or is it restarting; i.e., power down then power back up by itself? — Jerry Wheeler