Flashtool makes things easy. Don't have a J myself, I have XZ and haven't had any issues with other Xperias using it.
Thanks for the advice.
After a few attempts, problems and reflashing of the sony firmware, I managed to follow the instructions.
Can I use this version of cwm to flash PA3 4.1.2? Some of the posts on xda say that this version of rooting and cwm can't be used to install custom ROMs.
I'm in the process of joining xda so I can post the question there, but I thought I'd ask it over here too.
(Edited) As a new member of XDA, I can't post a reply in that thread.
Am I right in saying that the cwm team haven't developed a recovery image for the Xperia J? If that's the case, can cwm be used to flash custom ROMs?
I tried flashing PA3 4.1.2 (first wiping data, cache partition and dalvik cache). CWM claimed the flash was successful but the phone wouldn't start up on reboot. I ended up flashing a sony firmware to get the phone to work.
I've since read that a data wipe before the reboot might be needed. Which wipe(s) would that be?
Edited by nicjoco, 02 May 2013 - 12:47 AM.