[TRE_588]

JTAG is a low level hardware feature that allows people who know how to use it, and have the equipment, to bring phones back from the dead. JTAG can handle just about any brick situation short of a physical hardware issue.

You'd have to open a device to have access to it's motherboard/logic board/whatever you'd like to call it... but if you're out of warranty or have voided your warranty, it's about the only way to revive some devices... short of completely replacing them.

We also use jtag to mod Xbox and ps3's to by pass some system blocks