The PS4’s boot ROM contains a one-time programmable fuse set. Each time you update, Sony burns a new fuse. When you try to downgrade, the system checks these fuses. If the firmware you are trying to install has a lower number than the burned fuses, the PS4 refuses to boot. This is called . No software trick has ever bypassed this permanently on retail hardware.
A known developer on Twitter (now X) released a proof-of-concept payload that allows on 13.02 via a patched version of the BlueDog exploit. This is not a downgrade, nor a full jailbreak. It enables: ps4 downgrade 1302 new
The “1302” part becomes irrelevant—it is merely the starting prison from which you are escaping. The PS4’s boot ROM contains a one-time programmable