If I mess around with settings in the secret menus on my phone, can the changes be undone with a factory reset?

[Pianodude58]

Yes, a factory reset restores the phone's settings and data to their original out-of-the-box state, deleting all personal files, apps, and customized settings.

[realaud]

If you remember which settings you changed, you can just go in and change them back. Never make changes if you can't remember what you did and only change one setting at a time.

[ChewbaccaChowder]

It's too late. 😥

[officialguy]

And, never make changes when you don't know what they are!

[Anonymous]

Are there settings that are saved even after a factory reset of Android? Like could a phone ve ruined forever because of secret menus you can access with dialer codes?

[realaud]

Then you have two choices. Go back to those menus and try to figure out what you did and undo it, or factory reset your phone. And on the future don't change things you don't know. Those menus are hidden for a reason.

[ChewbaccaChowder]

What if I fiddled with the menus in *#0011#?

Will a factory reset fix anything I might have messed with, or do I need a new phone?

[realaud]

If you factory reset your phone, all settings are deleted.  If you restore your backup, you will get the same settings that got messed up, so if your aim is to unmess it up, you will have to reset and set up your phone from scratch OR remember what you did and undo it.  You can do a selective restore and not restore the settings, but restore everything else including your homescreen layout and apps.

I am unsure as to whether you can restore your older settings, by doing a selective restore of just the settings over what you have now.  If you can get the old settings back this way, you would not have to reset your phone, but the old settings still being intact, would be dependent on whether you made your changes before or after the most recent backup.  If your backup was made last night and you made your changes today, you can restore your old settings.  If you made the changes yesterday, restoring your settings will give you the same settings you have right now, and whatever that's doing to your phone.