Welcome to iRV2.
If your coach is on a Freightliner chassis , like mine , the correct name for the switch may be " ICC Flash " switch, I can't say what the acronym stands for , but my coach has one ( up/on; down /momentary ) dash label ICC Flash.
If your coach is on a Freightliner chassis , call their free help line with you serial number , maybe they will have info to share, as to original manufacturer.
1-800-385-4357
1-800-FTL-HELP