Good evening all,

New member here, looking for some senior insight on an electrical issue surrounding my headlights.

I have a well used, but loved 1979 C3 Corvette and have been doing upgrades, as time allows wanting to "freshen" her up. 

My first issue was the lazy headlight buckets, which I quickly remedied with some aftermarket motors.  When I began to tear into her, I realized that if you're going in this deep, might as well go a little deeper and take the bull by the horns, meaning I was replacing not only all the vacuum jazz for electric motors, but added new LED lights, aftermarket headlight wiring harness (which ties into original / plug n play per se), new headlight switch and associated mounting brackets/hardware for each light, since most of it was broken and or brittle to the touch etc.

Anywho, after the install, I noticed that my headlights only worked on hi-beam.  When I switched to low-beam, I have all 4 lights looking me dead in the face laughing....nadda.  Click dimmer switch to hi-beams and voila...all 4 are on shinning bright.  

I thought the dimmer switch may be a culprit, so I bought a new one (mounted on column).  Before going through the PITA  true install would be, I just connected it to the existing harness as a "soft mount" and clicked with my thumb.  Lights still act in similar fashion....no low beam, but high beams are brighter than the sun.

With the new after market harness, it has 2 relays.  I swapped both of them for brand new and tested relays, with no change in symptoms...so I am stumped.

Any idea there fellers?

New LED lights...

Verified dimmer is good...

Swapped relays for new/tested and known good ones...

Checked all grounds...

Checked inline fuse...

I am truly stumped.  Electrical is not my strong point by far, but was curious if anyone had an idea, or place to poke next.

Many thanks in advance!

Are these ebay special led headlights? 

Yup...they are.

Take it that maybe these have been proven in the past to have complications on C3s?

Thanks for the quick reply!

I have a friend that bought so called plug and play LED headlights for his 95 C4 and they didn't work like they should.  I think he got a hold of the seller and the seller sent him new ones that worked.  Chinesium parts are hit of miss unfortunately.

Hmmmm..well its definitely a possibility thats for sure.  I guess i can always go buy a halogen and swap it amongst the buckets to rule in favor of a potential true diagnosis.  Too bad I dont have the stockers...got flooded 2x with Helene and Milton.  Vette was moved to a safe location...parts bin got a tad bit wet.  Ha.  

Thanks again man.  Ill be sure to report back for the forums content.  

Good. I hope it's just the headlights.

Not to be judgmental, but do you have the bulbs and sockets in the correct position? 

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Hello

I "assume" so...I wasnt aware that they had to " clocked" a certain way.  Theyre 4 sided LEDs...Id figure they would illuminate one way or the other.  Judgemental can 100% be a good thing feller! 😜

Hi, one bulb has two prongs for wires, one has three.  Not sure about L.E.D., but the O.E.M. ones are positional. 

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Well...got a somewhat good update for the thread.

After reviewing some stuff online and revisiting the the harness...I decided to go back to stock utilizing the factory wiring harness and new LED lights...works like a charm, so it isnt the lights per se.  Lights work like intended with factory wiring.

I contact customer service in regards to the harness and they advised the harness is not intended to work with LED lighting options.  

So go figure...ugh.  at least Im back on the right track and not sitting here scratching my head all day and night again.  

Ill run em on the stock harness and monitor for heat at both the light connections and headlight switch.

Thanks 

Who Ray!  Glad it all worked out for you. Not sure if heat would be a factor, as the L.E.D.s would pull less amperage and run cooler. What, if any reason was there that the new harness would not work? 

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