Make sure the ISS has been completely re-powered after changing the ID to 3.
Turn on the console, display should be <Receiving From> press <Done> once, display should be 1 above the line and OFF below the line, if not OFF then press the Down Arrow to turn the ID OFF
Press right Arrow, display should be 2 above the line and OFF below the line, if not turn OFF (down arrow)
Press right Arrow, display should be 3 above the line and use the down arrow to display ON (ISS) below the line
You could also then check all the other Tx ID's are OFF in the same manner, then press Done and display below the line should show Retransmit OFF
Forgetting the other setup items at this point, press and hold Done until the normal display lights up, you should start to see some reception on ID 3 after a little while.