Disconnected Green/Yellow Vacuum Line

[fredyarvin]

I have an 84 300D with a vacuum line that is disconnected and no obvious place where it should have been connected.

It is the green/yellow line that comes through the firewall. I have confirmed that it goes into the climate control system. According to the vacuum chart, it should go into a check valve with a red/grey line from the vacuum reservoir. I cannot find the red/grey line anywhere.

The only check valve that goes into the firewall at the same point has a yellow and a yellow/black line. I traced the yellow to the front driver's door, and the yellow black goes up towards the instrument panel then I lose it.

My climate control buttons always send the air to defrost and the outside vents, which I have read is the defaul position, so possibly it is not getting any vacuum due to the disconnected line.

Does anyone know where this green/yellow line should be connected?

Thanks.