I have two 3com
I don't know anything about these units, nor do I have time to source any docs for you, but maybe you can try connecting a PC directly to the port your patch panel is connecting the the switch from, you can at least see if that port is working.
My next and only other suggestion is to invest in a "LAN cable tester". In my area, you can find cheap ones for U$20.
The tester will allow you to check connectivity between any two ports, and allows you to test both patch links and individual CAT5/6 cables.
3Com Computers &...
on Nov 22, 2017