hi there, i have nearly the same problem. my ps3 slim is 3.42 and i am now in the factory mod, but when i insert the flash disc that contain the two files (Lv2diag.self) and (PS3UPDAT.PUP) modified 3.41 pup file then i power on the ps3 it does not show black screen and it power on and shows the factory service plz help.
and it is written on the back on my ps3 model NO (CECH-2004B)
same problem in my CECH2001a.. stuck in the factory mode. i was thinking maybe the ps3 doesnt recognice my usb flash drive (8gb).. i tried in many way... download the 3 downgrade files... reformat my USB drive using dos command... enterchange my flash drive slot in my ps3... nothing works... pls help.
Same for me. Just bought a PS3 320GB 2500GB FW3.50 in Japan and also I cannot downgrade with this method (using Rockbox and a iPod Mini 2G). After getting into service mode and trying to apply the firmware of 3.41 modded, the HDD is active for 20 seconds then stops and the Green Light starts linking. Very sad, as I bought the PS3 2500 after reading everywhere that all FW3.50 and CECH 25XX systems could be downgraded.