Does anyone have a diagram of how the headlight wiring should look. It looks like the last owner of my vette did some "handi-work" cutting and splicing the wires. It seems like my headlights are not as bright as they should be and when I turn the brights on, all 4 lights go bright instead of just the inner 2. Any help would be appreciated. I really dont want to buy a $300 wiring harness.

Oh and I have a 1980 by the way!

 

For what it's worth, while on dim, only 2 headlights are on and all four are on when brights are operating...

I'll try to remember to post a copy of the shop manual wiring when I get home tonight.

 

I thought when the lights were on dim all four lights were on, just that 2 were brighter, and 2 were really dim. Then the opposite on bright.

 

Avette4me, is correct. You should have the two outer beams working when on low. When on high, the two inners come on along with the two outer. Sounds like your lights are working correctly.

 

ok, but it looks like one side is dimmer than the other. What could be the reason for this. Also, when in High-beam it looks like my interior lights are lightly pulsating. Is my alternator not putting out enough amps?

Thanks

 

I would first replace both hi-beams (inner bulbs) as it is typical for them to appear low when they are on their last leg.

Also while replacing them I would clean the wire connectors.

And I would put a volt meter on the back of each buld to see what kind of voltage I was getting up at the back of each light.

You might solve the problem or at least know where to go next.

 

Power for the lights has an incredibly long path. Generally, runs from alternator to starter/batter connection to fuse box to switch to lights to ground to battery. What starts out as 14v at alternator becomes 11-12v at the lights.

Solution is to add two relays (one for hi, one for lo) that are controlled by the old wiring and provide power directly from the alternator to the lights. You will usually end up with 14 v at the lat and about 14v at the lights if you use big enough wires. This will provide much impoved lighting.

At idle, your alternator puts out less juice so your lights will dim. You should see mine when the fans are running.

I have an address for a good article on wiring in relays and I'll post it when I get home.

 

Click on my URL below, I have a pic of the headlight relays that direct 14 volts directly from the alternator to all 4 headlights. You talk about bright.

 

Pete, I think it was your car that got me going down this road. BTW, your pics aren't showing.

Anyway, here is the article. It is from a Rover website but 4 headlights are 4 headlights. For relays, I am looking at quality Hella waterproof ones from www.route66supply.com. More expensive but nice and the same as my fans use.

http://users.mrbean.net.au/~rover/headlamps.htm

 

I appreciate all the info, but I'm still wondering if anyone has the exact diagram of the wiring?

Thanks!

 

I would email you the 1980 diagram , but you will get much more out of going to the Norwegian C3 site, http://iotech.no/corvette/index.htm
There's a full set of GM workshop manual electrical diagrams for the 80 there. I feel your pain, by the way - the headlight wiring on my 80 was a total mess. I only realised this when the whole system shorted out and melted the switch one dark British winter night at a motorway service area 50 miles from home.
I basically had to rewire the whole front end and fit a new switch. What a job! I took the opportunity to fit relays (like some of the above posters have mentioned) to feed the lights with a full 14v off the back of the alternator. Much brighter headlights and dash lights, I was very pleased with the outcome, even if it was a bloody awful job.
I'm happy to give you a few pointers as you tackle this job, if you like...