Set: Home->Config1->RS232-Routing->(LAN->RS232)

Set Home->Advanced option->Power Save = Mode3 (turn on/off by itself based on video signal detection) or Mode 4 (always on)

Home 1888->Settings->Signage Display-> Server Settings->SICP network port

     - enable SICP Network port

     - ensure it is set to port 5000

Check the Home->Configuration 2->monitor ID is set to the value that will respond to your SICP command