As an additional safety measure, we will perform an additional check for custom firmware. This is because using this method when custom firmware is already installed has a risk of bricking the console (rendering it unusable without recovery methods like [ntrboot](ntrboot)).

1. 将主机关机
1. 按住 “Select” 键
1. 在按住 “Select” 键的同时按下电源键开机
1. If the check was successful, you will boot to the HOME Menu and you may proceed with this guide
1. 将主机关机

If you see a configuration menu or the console immediately powers off, you already have CFW, and continuing with these instructions may BRICK your device! Follow [Checking for CFW](checking-for-cfw) to upgrade your existing CFW.
{: .notice--danger}