Here is a tutorial of how to make a Pandora Battery (Which can downgrade or unbrick any PSP [Slim or Phat]).
REQUIRE:
1) PSP (Slim or Phat)
2) CFW (Custom Firmware, Example: 3.xx-m33-x)
3) MemoryStick Pro Duo (128mb or higher)NO HIGHER THAN 2GB BECAUSE YOU WILL BE WASTING A MEMORY STICK
4) PSP Battery
Ok with this items you are ready to create a Pandora Battery
STEPS OF MAKING A PANDORA MEMORYSTICK:
1) Format memorystick using your PSP (slim or phat)
2) Connect your PSP to the Computer
3) Copy pan3xx Rev 3 to GAME folder (Download Here: Pan3xx Rev3)
4) Copy UPDATE.pbp to ROOT (Download Here: UPDATE.PBP)
5) Disconnect the PSP from your Computer
6) Run pan3xx Rev3 press R+X (to format and repartition)
7) Press L+R+X (to proceed repartition, all files will be deleted...)
8) Connect the PSP again to PC, create a PSP folder, inside the PSP folder create a GAME folder
9) Copy Pan3xx Rev 3 folder to GAME folder
10) Copy update.pbp to ROOT
11) Copy 150.pbp, 340.pbp,and 371.pbp (If you want the 371m33 update) or 380.pbp (if you want the 3.80m33 update) to the root of the memstick
(Download Here: 150.PBP, 340.PBP, 371.PBP, 380.PBP)
12) Copy despertar del cementerio to game folder (Make sure you do not have a custom theme or your PSP might brick)
Option 1:Despertar Del Cementerio 3 (This version is for if you drag the 371.pbp to the root of your psp and if you want 3.71m33)
Option 2: Despertar Del Cementerio 4 (This version is for if you drag the 380.pbp to the root of your psp and if you want 3.80m33)
13) Create GAME371 and GAME380 folder inside PSP folder
14) Copy open source pandora battery tool to GAME371 and GAME380 folder (Download here: Open Source Pandora Battery Tool Ver.5) [Used to convert battery to pandora battery OR it can also be used to return the battery back to a regular battery]
15) Disconnect the PSP from your Computer
16) Run pan3xx Rev 3 (make sure you have update.pbp in your memstick root...) press X , it will install all the necessary files.
17) Wait until pan3xx Rev 3 finishes installing the files on your memstick, then from the menu press L+X to install ms0:/MSIPL.BIN, and wait when asked press L+X again, wait for program to exit
(Congratulation!!!You now have a jigkick memstick. this will upgrade/modify your psp and will install 1.50 directly to your PSP)
If you want to have Universal Unbricker V3 or V4 (update or unbrick to a CFW) continue on with step#18...
18) Run despertar del cementerio, wait until it finish (it will update and overwrite 1.50 to universal unbricker from your jigkick)
19) Reconnect your PSP to your Computer delete the update.pbp from the root of your memstick. (but if you only want to have pandora with 1.50 installer, dont delete update.pbp from root. just run pan3xx rev 3 again and this will update and overwrite your V3 or v4 memstick with 1.50) you can also use this to downgrade back to 1.50
20) Now have a custom made Pandora magic memstick (you can also use this memstick as a regular memstick to store and play your ISO/CSO games)
OPTION: You can also put CFW 3.90 M33 update to your memstick and update to 3.90m33
Download Here: 3.90M33 UPDATE (You can update to 3.90m33-2 with the network update, but make sure the option in the configuration of the recovery mode is enable and that you have more than 75% of battery)
Now with the Memory Stick ready you are ready to make the Pandora Battery
STEP FOR MAKING A PANDORA BATTERY:
1) Run open source pandora battery tool ver 5 from your psp, from the menu press X and select make battery to pandora (service mode) and exit.
2) Turn off your PSP, remove your battery and memory stick.
3) Insert your magic memstick, then insert your pandorized battery (your wi-fi and LED will flashes and on your screen your psp will show you a message; asking you to press "X" to start flashing your PSP (revive your psp back if bricked)
HOW TO RETURN A PANDORA BATTERY TO NORMAL
1) Insert your PSP charger to PSP and turn on your PSP without the pandorized battery
2) Once you are on the XMB, re-insert the magic memstick and your pandorized battery
3) Run open source pandora battery tool ver 5, from the menu press X and select make battery to normal mode and exit.
4) Now turn off your PSP, remove the memstick and battery (so that it will not recall the service mode)
5) re-insert your memstick and battery and turn on your psp. Your battery should be back to normal again.