GT-i9505 repair boot problem

Hello to all…

I have a S4 GT-I9505 who does not turn on, I connected the jtag and started the recovery process ..
That hangs on this screen:

Code:

Welcome to Medusa Box Software version 2.6.1
Selected device model: Samsung GT-I9505
Connecting. Please wait...
Checking data...
Medusa JTAG Firmware version 1.1.0.
Medusa JTAG Hardware S64 revision B.
Detected TAP ID: 4BA00477, IR Length = 4.
Detected TAP ID: 2071B0E1, IR Length = 11.
Medusa JTAG Firmware version 1.1.0.
Medusa JTAG Hardware S64 revision B.
JTAG speed  : 1000 KHz.
VREF level  : 1.78 V
CPU        : Qualcomm APQ8064T
Core ID    : 2071B0E1
ERROR[004]: Medusa Device Server did not replied to HELLO command.


Hardware problem?:confused: