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I’m having an issue with my headlights staying stuck open.
I was driving my ‘76 down a road and there was a c5 driving in my direction. “Oh ****! Gotta wink the headlights!” I said. Well the c5 corvette beat me to it, and my headlights slowly opened in response after some delay (as they had usually been doing), but they wouldn’t go back down when I pushed the switch in.
Upon further inspection, I am able to hear the vacuum working to raise and lower the headlights with each pull and push of the switch, and I tried to pull/push on the the little bolt join under the headlights to manually close them, but they still won’t close. They are stuck open.
Does anyone have any idea what the problem could be? For now I’d like to hear some obvious (ideally inexpensive) fixes. This is my first corvette of any kind and I just bought it 2 weeks ago.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
to manually close then you need to pull down on the linkage. Follow the link to the Willcox troubleshooting guide. It usually is a bad headlight switch or a bad actuator relay. Those re the 2 items I replace repeatedly. If you have a vacuum gauge you can unplug the hoses going to the relay and see what you are getting for vacuum. THere should be constant vacuum that is switched on the verticle stem and the switched vacuum that comes from the headlight switch to pull the plunger up. It is springloaded down. If the link doesbt help reply and we will walk you though some tests. If you dont have a mighty vac you should look at getting one. hearing vacuum leaks with the motor running is very difficult. I have a motorized vacuum pump from harbor freight that I use to apply vacuum to the system, then shut off so I can hear the leaks....it works great
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
with vacuum applied or engine running take vacuum reading at manifold hose with gauge before "T" all readings below should e the same as manifold vacuum, if they are not, unplug the hoses at the T and plug one side to test the other. A low reading obviously shows a leak.
test for vacuum at tank number 2 fitting, unplug hose, use gauge. should be the same as the manifold
test for vacuum at tank both number 1 fittings, unplug the hoses at the relays and plug one to test the other, should be the same as manifold
unplug black and blue hose at override switch and test, should be manifold pressure and cycle with switch.
unplug balck and white hose at the T near relays and test
Testing the relays should be with the other relay black and white hose blocked and the headlight switch having vacuum applied. vacuum should cycle as headlight switch is operated from the green to the red hoses.
You can also test the relays or bypass one really to operate both headlights by adding Ts to the red yellow and green hoses. 68 and 69 had only one actuator relay so this can be a temporary solve until your new relay arrives
Stuck headlights with (working?) vacuum system
