SQL server 2012 – dtexec / val / proj my.ispac / pack my.dtsx / rep v returns immediately without any message

I am trying to configure a command line call to dtexec to validate packets, using the project model. I'm calling dtexec like this:

dtexec / val / proj my.ispac / pack my.dtsx / rep v 

Although the real roads to the ispac and dtsx are longer. When I run this, all I see in the console is:

Microsoft (R) SQL Server Execution Pack Utility
Version 11.0.7001.0 for 32 bits
Copyright (C) 2016 by Microsoft. All rights reserved.

Started: 10:40:01 AM
PS D: >

Everything happens in less than a second, which leads me to believe that he did nothing. And messages of any kind are not issued, although I asked for detailed reports.

Any ideas on how to make this work?