Unfortunately this highly depends on the services (e.g. FTP, SNMP, HTTP) the printer is exposing and if the exposed data is helping us to detect the printer.
But basically you can try to run the following calls (Linux system required) to see if they are giving you any output and post the output in here after removing any sensitive data:
Telnet:
nc -vvv $ipofprinter 23
FTP:
nc -vvv $ipofprinter 21
SNMP:
snmpwalk -v 2c -c public $ipofprinter
HTTP:
curl -i http://$ipofprinter
In this case it is not a matter of which VT is causing the issue as every VT (there might be hundreds) sending some data to that port will cause your printer to print out some text. If you have a linux system at hand you can even print some text from command line like e.g.:
echo "Hello world" | nc -vvv $ipofprinter 9100
and your printer will start to print out this text.