There's no way to enable ADM remotely.
Android Device Manager is normally on by default under Security - Device Administrators. If you logged in on a pc and it's not there though, then it would be off.
If the device is named in the ADM screen, then as far as I know, you only need Location on when trying to "locate" it.
You can still send instructions to Lock or Factory reset it while it's off. It will activate when turned on and it has a data connection.
If it was stolen and they wipe it you are out of luck there (they would want the device more than your information). You can block the imei with the help of your carrier. I would change the passwords you are worried about.
You can leave a message and a contact number dial button with the Lock function, if someone finds it and wants to return it.
05-02-2015 09:30 AM