Got an old iPad mini 1, new battery, new screen, new LCD, and found it workes really fine, apart from the Real Time Clock now working after the iPad goes into sleep mode. Turning it on again (with home-button or on/off button press), and checking the time, will show the last time it either got from the internet time server, or manual settings, and closing settings again.
I cannot imagine what could be wrong, the clock shows normal, with updates every minute when the iPad is kept on, but since that is really an option, something else must be wrong. Feels like the clock is working, but somehow doesn’t write it into FLASH memory or …
Some questions I have: does the iPad mini use an outdated RTC server on the internet? If yes, can I change it somehow?
Could this be a hardware problem? A frequency signal to the RTC that works when the display is on, should not be different from a frequency signal to the RTC in sleep mode, but who knows?
The iOS (iPadOS) is the latest possible 9.3.6, would downgrading solve the RTC problem?