Chosen Solution

bought a used PS4 and it won’t allow any sort of input device to connect to it. It provides power via the USB ports but it does not want to connect anything to it. Can’t even factory reset the HDD because it doesn’t want to use it.

If you’re only getting power and no data exchange, then you should try swapping out the cable you’re using. It might sound simple but I’ve tried at least 5 different cables before I found one that worked. Some cables are only designed for power and so won’t be able to connect the device you’re plugging it into as there is no communication between the devices, only power output. Also how do you mean it doesn’t want to use the HDD?