I agree — It should not be leaking. I just had my car into service for a similar warning message. The Service Center found that both the 3-way and 4-way valves were leaking, and replaced both. Then when they tested the system, they found another issue and replaced the “thermal controller” in the cabin HVAC system. Fortunately, I have an Extended Service Agreement. But in any case I was glad that these issues were addressed. You don’t want to be stuck someplace with a coolant system that has leaked so much that the battery overheats or something.