See Figure 1
Vacuum is supplied by the intake manifold and is distributed, by a valve through an orange hose, to a check valve which is used in the vacuum source line to prevent vacuum from leaking from the reservoir back through the engine.
A white hose connects the check valve to the vacuum reservoir tank which stores enough vacuum to permit limited operation of the headlight covers without the car engine running.
Another white hose comes from the check valve and supplies vacuum to the center connector on the distribution valve mounted on the back of the headlight switch. When the switch is pulled out, it actuates the distribution valve and supplies vacuum through the green hose to the open side port of the vacuum motor and opens the headlight covers.
When the switch is pushed in to turn the headlights off, it actuates the distribution valve and supplies vacuum through the yellow hose to the closed side port of the vacuum motor and closes the headlight covers.
A by-pass valve is provided between the headlight switch and the vacuum motor to vent the system and allow the covers to open when they will not automatically open.