Gunakan TWRP atau Terminal emulator ( khusus untuk yang sudah root)
Lalu ketikkan perintah dibawah ini secara berurutan,
rm /efs/FactoryApp/keystr
rm /efs/FactoryApp/factorymode
echo -n ON >> /efs/FactoryApp/keystr
echo -n ON >> /efs/FactoryApp/factorymode
chown 1000.1000 /efs/FactoryApp/keystr
chown 1000.1000 /efs/FactoryApp/factorymode
chmod 0744 /efs/FactoryApp/keystr
chmod 0744 /efs/FactoryApp/factorymode
reboot