It is possible to see if the PLM and the EZIO8SA are communicating by observing the LED pattern on power-up. For PLMs prior to version 4.X, the LED turns on, then off successively 6 times, then off again for a longer period, then it finally stays on. In some cases when the external EEPROM is recognized, the pattern is: on, then long off, then solid on.
Please call the hotline and we can help you or determine what part to ship back for repair or upgrade.
In PLM version 4.A and above the LED is dimmed so the pattern is harder to observe. However a long off before the LED goes on solidly is discernable.