Do you think that you have brick your phone? Your Phone Dead? You don't have JIG. Try steps below. It might fix your problem.
1. Battery out. 4secs or more. Battery in (Remove SIM card and SD Card to be saved)
2. Volume DOWN + Home + Power Button. Hold it EXACTLY 5 SECONDS!
(NOW YOU IN DOWNLOAD MOD)
3. You will see or hear nothing! but remember you are there!
4. After when you got in download mod if you remember you need to "Press Volume UP" to confirm it. So press Volume UP and wait 2 seconds
5. Connect your mobile to the PC (Desktop ODIN Running). You will hear the sound. Which mean your phone connected.
6. Flash any stock firmware as you like....
Remember everything working! You just don't see
Do it until it will work.