1, first open the phone Settings page, click \"system\".
2, then select the \"About Phone\" option, find the version number and connect and click 5 times.
3, then use the charging cable to connect the phone to the device that needs reverse charging, and return to the desktop of the phone.
4, then pull down the screen, click \"View more\" option, then the page pop up USB connection, click \"reverse charging\" can be.
There are several reasons for this
1. The first one is to check whether your mobile phone model supports reverse charging, which is generally available for new mobile phones, and old mobile phones have no change function
2. Reverse charging can be used only when it is enabled