I just bought a 2006 C6 and quickly found out that it has a few electrical issues.
HIGH BEAMS - they seem to work intermittently. I don’t know if it’s heat related but I drove it tonight and when I first got in, they worked. After driving for 15 minutes they would not work. The light on the dash illuminates but the high beam bulbs do not.
HORN- I tried to honk at a buddy tonight and no horn. Not sure if that is intermittent but it didn’t work the one time I was going to use it and 30 minutes later at home, still inop. I know that it also worked before actually because when I first got the car, it would honk to confirm doors locked and I changed it in the settings to turn that off. Turned it back on to test and horn does not work with doors locking.
FOG LIGHTS - also intermittent. They have worked (I’ve seen them on) but when I started troubleshooting the high beams, the fogs would not illuminate. The light on the dash also indicates fog lights are on.

I checked the fuses under the hood for everything listed and all are good. I swapped one of the known working mini relays (parking lights are working) into the positions of all 3 non-working items and none of them would work.

Any other ideas?
Thanks!

 

One thing for sure is when the high beams are on the fogs will turn off automatically.

 

Check your battery. I had all sorts of electrical gremlins in my 09 so I took it to Auto Zone, had them install a Duralast, and all of the electrical gremlins disappeared!

 

JFYI there was a recall on C6 to repair a weakness w/ fuse block wiring, problem area's underneath box.
Due to heat cycles a wire was prone to break, happened especially w/ vehicles in hotter sunbelt states.
Wire would cause inoperable HLs, intermittent w/ some in the beginning until finally crapping out altogether.

Fairly easy fix by dealer or DIY jumping-out affected wire, must remove/disassemble fuse box to access underside though.
Many videos detailing procedure are out there.

A GM dealer can check VIN to determine if this fix was ever done.
If it hasn't shouldn't cost a dime and just may solve the HL issue.

 

First off, check the ground wires connection for the High beams and the fog lamps. The electrical circuits are all ground initiated, so a bad or weak ground connection
will cause what you describe. The right high beam and fog lamp use the same main connector ground G102 found on top of right frame rail. The left high beam and fog lamp connect at G101
found on the left frame rail, but the main ground also connects to G102 as well.
Good Luck

 

There was a GM recall for the C6 headlights, but I believe that was for the low beams?

 

There are several recalls on different parts of the electrical system in the C6. I went to have my emissions test done on my 09 in July. The car was running fine. When the guy checking the emissions plugged his diagnostic tool into the car and told me to start it back up, it did nothing. He pulled his diagnostic tool and it had thrown a code - I don't remember the code. When he plugged the connectors back up that he had unplugged the car started right up but the check engine light, which wasn't on when I pulled in to do the emissions check, was on. I went home and researched the code. Chevrolet had a bulletin on it with specific steps their dealers needed to take with this part of the electrical system before they replaced it completely. There was no time frame on this free repair.

The C6 has more electrical issues than any of the three other generations I've owned combined, and I've had a Corvette in my garage for the last 26 years.

 

Thanks for all the replies!
I looked into the recall status of my car (VIN based search) and it looks to have no open recalls. Not sure if the VIN check can see if the recalls were completed or what exactly it's looking for. I'll check the grounds as well, thanks for that!

Here's the strange kicker. So I troubleshot it in my driveway within an hour of driving it. The High beams/Fogs/Horn would not work. Checked all the fuses and relays associated with these three systems and all looked good. Today, I went to drive it but first checked these systems and they all worked! What the....? I am so confused. Could it be a heat related issue? Like when the engine compartment is warm, there are electrical issues? I checked it again after a 15 minute drive and all still worked. UGH
I saw that the low beam recall can be related to a heated up engine bay but nothing else I saw in searching looked to describe my issues.

So weird!