"PHONE" message is displayed automatically every time when mute PIN is activated. It doesn't go throught any CAN or K-Line so coding really doesn't matter. RNS-E will not support 3rd party interfaces, but you could play a little to display PHONE on your DIS.
It's very possible that coding DIS for RNS-E arrows could actually void PHONE message display, but I'm not 100% sure of it.
It's very possible that coding DIS for RNS-E arrows could actually void PHONE message display, but I'm not 100% sure of it.