There are lots of tutos out there including here on wololo.net, but they are a bit outdated. Note that this tutorial is about upgrading to firmware 3.60, not downgrading to it!
If you’ve installed firmware 3.61, 3.63, or above, you’re pretty much sc*** for now and will have to wait until a new hack is released for the PS Vita.
However, it is complicated and somewhat time consuming.
This is a little “how to” for updating UConnect firmware yourself.
Then reboot and you should be good to start this tutorial.
While most customers will wait to visit their dealer to upgrade the firmware of their UConnect systems, it’s not required for those who have connected USB drives in their recent Chrysler, Jeep, Ram, or Dodge.
These include a small bootable Linux distribution and a collection of all firmware (repositories) for a specific server model.
The updates are done automatically after starting the server from the corresponding image and can take up to 1 hour to complete (when running it locally or on the same physical network - remote may take considerably longer).
Note for those of you who have downloaded (but not installed yet) firmware 3.61/3.63, or anything above 3.60: you can allegedly delete it from the bubble at the corner of your PS Vita.
This firmware update process is done entirely at your own risk.
If performed correctly, there will be no loss of system or user data on the drive.
This tutorial applies to people who are currently on lower firmwares and want to go up to firmware 3.60.
Yifan Lu, one of the authors of HENkaku, wrote a system on the HENkaku servers to help you simply upgrade to firmware 3.60: If you’re having issues with this easy way, check the detailed steps at the source here.