light covers go up, but not down

[Schuler]

On my '69 when I turn the lights on they work just as they are sopposed to. But when I turn them off the flaps don't come back down. Is this a problem with a vacuum line or what? There is a small ground strap on the grill that is not connected to anything. Is that sopposed to be screwed to the radiator support?

[TylerCharger69]

either there is a leak in the light switch vacuum pot...or you may have your vacuum lines crossed ,  or there is a leak at the vacuum canister  (underneath battery tray)   are the doors real slow to open up??

[Schuler]

They open up quick. The canister is ok. (just put it in last summer) They closed before the car was inoperable for 8 years and haven't worked since the car was put back together.

[resq302]

I just had the same problem.  It turned out that my part that was bad was the vacuum switch on the headlight switch.  If you do a search on headlight vacuum switch, you will find a guy on here that came up with an ingenious way of rebuilding them and making them into a serviceable part.