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I have an iPad Pro (no repairs done) AND an iPad Air 1 with screen replacement. Both have random Shut downs at 100% charge and then when it reboots the battery indicates 1% is there any SMC reset for iPads? It seems to be an iOS issue. I have done erase all content and also a dfu restore to no avail. No apps at all are installed now it is fresh restore I think this is a power management issue. Please help :)
For the Air 1, have you made sure the battery is connected to the board properly? There is one longer screw used for the battery connector. If the housing is bent near the battery connector area it can cause these issues too. Usually this means the battery is not getting a good connection to the logic board.
