I checked and his #4 colors match. I am not sure when/why the diverter opens, or what the purpose is. The climate control manual does not explain that technicality very well. To me, it seems to force air through both the condenser AND heater core when close, but when open it may allow air to bypass the heater core (which sits in front of the condenser). That's a total guess though, and I don't understand how that would affect operation anyway under normal/max cooling (not bi-level).