Jailbreaking a CFW compatible console with the PS3 Toolset Flash Memory Manager.
1. Make sure you are on OFW or HFW 4.82/4.83/4.84/4.85 or 4.86, if not, update to one of those 5 supported firmware versions.
2. Open the browser & load the PS3 Toolset ** www.** ** www.ps3xploit.net > D... (NEW URL = http://ps3toolset.com)/bgtoolset
3. Go to the Flash Memory Manager tab, always keep FMM Strict Mode enabled.
4. Make sure FMM displays "CFW compatible"
5. Dump your Flash Memory on a USB key for backup purposes.
6. Use the Flash memory patch option "Load patch via https"
7. If validation is successful after download, apply the patch.
8. If patching validation is successful, reboot the ps3.
9. Download and install any CFW which version is equal or higher to the current OFW/HFW version.
10. On reboot, install Rebug Toolbox & enable QA then reboot.
11. Now you can downgrade the firmware. If ever you started the process on OFW/HFW 4.85 or 4.86 & you wish to use Rebug REX & not Rebug Lite, you can install Rebug REX 4.84 & toggle CEX/DEX mode.
If you get a validation error at step 7, do not try to continue to the next step, FMM will not let you anyway as long as FMM Strict Mode is enabled.
If you get a validation error in step 8, DO NOT reboot.
In both cases, seek guidance in this forum.