The dash is digi-log, (Digital but analog displays) run by the engine control computer.. Several possible issues but if you read your owner's manual there is as TEST procedure. (I'm not in the motor home so I don't have the manual handy) but you hold a button or two and turn on ignition. The gauges should cycle in a pattern (Mid scale, full scale, zero, mid full zero or something like that) alarms will sound lights will flash, Then you turn off and back on. Failure to do the pattern = Proglem.
Possible issues include bad ground, bad connection, bad computer, bad display.
ONE issue I had with SOME gauges ONCE.....
Since this is all computer controlled.. when you first turn the key it does a POST (power on self test) Well I got into START before POST finished and as a result selected gauges did not work.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times