One Headlight Will Not ....
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Intermediate
Joined: Apr 2007
Posts: 36
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One Headlight Will Not ....
Using the normal headlight switch, healights go up and down OK - not together, but they go up and down when switch is pushed or pulled.
The problem is when I pull the vacuum overide inside, the left (driver side) can be pushed down, but the right will not budge - it stays up. Certainly do not want to force it. Otherwise all is good !
Any ideas about getting the left side to go down ????
Thanks.
Bob
The problem is when I pull the vacuum overide inside, the left (driver side) can be pushed down, but the right will not budge - it stays up. Certainly do not want to force it. Otherwise all is good !
Any ideas about getting the left side to go down ????
Thanks.
Bob
Pro
Joined: Apr 2001
Posts: 605
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From: las vegas
I am a little lost about your information. The override switch should be pulled down to get the headlights to open without the headlights coming on, that is the fuction of the override switch. After finishing on whatever part of the headlights you are working on you close the switch and the headlights should close (you probably will have to start the car to recharge the vacuum). The headlights are a deadman system, meaning that it takes vacuum to close em. So if one of them is not closing you have a vacuum leak, probably the diaphram in the canister. If you are going to keep your headlights in tiptop shape I would suggest getting a Silverline mityvac handheld vacuum pump. It is an indispenable diagnostic tool for the corvette headlight system. PS, even when the headlight system was brand new the right side always came up a little later then the left side, it is a design limitation of the system. Al
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From: Tampa, Florida
Le Mans Master
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From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Vacuum System
Vacuum starts at the manifold.
Then the line goes thru a filter.
Then the vacuum line splits into two.
One hose goes to the vacuum tank.
The other hose goes to the head light switch (vacuum goes thru the head light switch in the off position)
Than the hose coming out of the headlight switch goes into one side of the pull down switch. (vacuum goes thru the pull down switch when it is "up")
Then the hose coming out of the pull down switch splits in two again and those each connect to the top of the "relays"
The relays control the path of the vacuum.
If you pull the head light switch, you turn the lights on and you block that path of vacuum, the realy's now get vacuum from the storage tank.
When you pull "down" the pull down switch, you block the path of vacuum, and again the relay's get vacuum from the storage tank.
When you push the pull down switch "up" you restore the vacuum and the lights go down.
Short answer to Rfhall50, I would guess that you have a bad canister.
Hope that helps, PG.
