You might ask Spartan about what can trigger it. The chassis builder puts the light on the dash and decides what causes it to turn on, so it's not necessarily an engine code at all. Maybe it's engine in the broader sense, including cooling system, fuel system, etc in addition to whatever the engine ECM produces.
Former owner of 2004 American Tradition and several other RVs
Home is in the Ocala Nat'l Forest near Ocala, FL
Summers in Black Mountain, NC