C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

78 headlight problem

Thread Tools
 
Search this Thread
 
Old Aug 1, 2004 | 05:55 PM
  #1  
randy814u's Avatar
randy814u
Thread Starter
Melting Slicks
15 Year Member
 
Joined: Oct 2001
Posts: 2,320
Likes: 2
From: Salem Oregon
Default 78 headlight problem

Last time I used the headlights they opened and closed fine. Now they do not open. I just got through cleaning up a rats nest of wiring under the dash from the previous owner, fixing the turn, brake lights in the progress. I have good vacuum everywhere, so I do not think it is a vac. problem. Manual switch under dash opens them right up, and closes. I read the following on a web site and now I have a question I can not find a answer for on the web.

[FUNCTION: The headlamp switch turns the headlamps on and off and signals the vacuum components to open or close the head lamp doors.]

My question is, do they signal electrically, or is there a mechanical valve in the headlight switch? Headlight switch I have is only a couple months old and has been used 10 times give or take. Any info would be a welcome relief to this headache I have got from straining my brain working on it. Thanks in advance,,,Randy
Reply
Old Aug 1, 2004 | 07:44 PM
  #2  
hunt4cleanair's Avatar
hunt4cleanair
Le Mans Master
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2002
Posts: 5,228
Likes: 895
From: Myrtle Beach SC
Default

Originally Posted by randy814u
Last time I used the headlights they opened and closed fine. Now they do not open. I just got through cleaning up a rats nest of wiring under the dash from the previous owner, fixing the turn, brake lights in the progress. I have good vacuum everywhere, so I do not think it is a vac. problem. Manual switch under dash opens them right up, and closes. I read the following on a web site and now I have a question I can not find a answer for on the web.

[FUNCTION: The headlamp switch turns the headlamps on and off and signals the vacuum components to open or close the head lamp doors.]

My question is, do they signal electrically, or is there a mechanical valve in the headlight switch? Headlight switch I have is only a couple months old and has been used 10 times give or take. Any info would be a welcome relief to this headache I have got from straining my brain working on it. Thanks in advance,,,Randy
Randy...it's all about vacuum! There are a few headlight guides...I've found most of the few inadequate but they can provide the direction you need to trouble shoot. Dr Rebuild may be the best place to start and offers both guides and charts which are invaluable if you're a visual learner.

You mention the switch but I've never heard of the switch as being a source of mechanical failure. Probably need a shop manual to trouble shoot the switch. Of course...it may be that in the process of cleaning up the rats nest...you shorted something out or blew a fuse. Check it out first.
Reply




All times are GMT -4. The time now is 12:48 PM.

story-0
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-1
2027 Corvette vs The World: Every Model vs Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-20 17:58:41


VIEW MORE
story-2
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE
story-3
5 MOST and 5 LEAST Popular Corvette Model Years in History!

Slideshow: 5 most and least popular Corvette model years.

By Joe Kucinski | 2026-04-08 13:25:01


VIEW MORE
story-4
2027 Corvette Buyer's Guide: Everything You Need to Know!

Slideshow: 2027 Corvette buyer's guide

By Joe Kucinski | 2026-04-17 16:41:08


VIEW MORE
story-5
10 Things C8 Corvette Owners Hate (But Won't Tell You)

Slideshow: 10 things C8 Corvette owners hate, but won't tell you.

By Joe Kucinski | 2026-04-01 18:36:07


VIEW MORE
story-6
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

Slideshow: Should you add one of these incredible Corvettes to your garage?

By Brett Foote | 2026-04-01 18:14:05


VIEW MORE
story-7
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

Slideshow: Every Corvette Grand Sport explained

By Joe Kucinski | 2026-03-26 07:13:44


VIEW MORE
story-8
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!

Slideshow: Breaking down the 2027 Grand Sport, Grand Sport X, Stingray, and LS6 V8.

By Michael S. Palmer | 2026-03-26 13:48:45


VIEW MORE
story-9
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!

Slideshow: 5 reasons bad drivers crash sports cars & 5 ways to avoid a costly shame!

By Joe Kucinski | 2026-03-25 16:32:55


VIEW MORE