Hi Bill,
RV manufacturers rarely tend to match a specific color code and will typically use whatever is on hand and could even splice together different colors inside the walls so it's really just going to come down to testing the wire's function to determine if it's the correct wire for ground. If you were removing an old thermostat and the green wire was clearly labeled as ground then it would likely be safe to assume that it could be used as the ground wire when installing the Replacement... view full answer...