Topic: Horn issues...
in Forum: C3 Electrical
Hi all,
I've looked over a few previous posts regarding my horn promlem (it no work anymore!... at first it would occasionally give a limp buzzing sound when I pressed the button, now nothing). I've relized a few things from the other 'horn problem' posts:
1) I have no idea what the hell I'm doing,
2) I really, really need to buy a 1978 wiring diagram
3) I have no idea what the hell I'm doing...
With this in mind, I'm not sure if my 78 has one or two horns, if my horn relay also controls the non-working alarm, if my horn is bad, if my horn button is bad (how the hell does that come off anyway?), or if my horn(/alarm?) relay is bad (that's the blue square three pronged relay under driver's side dash, right?). What tends to be the common 1st thing to go on these systems?
(pretty neat how I asked a dozen questions in this one post, huh?)..lol I'm really not a wise ass, just a kid with a new toy!

Thanks. I'm looking up some service manuals right now. Corvette America seems to have the best deal on the Assembly Manuals, and looks like I'll have to get the 1978 Electrical Trouble Shooting Manual off ebay.
I found one of the horns (assuming I have two) - located right behind the washer fluid reservour, had to take that out to get to it. Had to remove the horn since it really isn't assessable for testing. I tested that one by touching the "-" side to the "-" side of the battery, and the "+" to the same on the battery.... DEAD. So now I guess I'll have to hunt the other horn down too. And as always, learned that just because the ignition is off, doesn't mean the "+" wire of the horn is dead... guess what? The engine block is gounded...LOLOLOL
Well, the Vette's all back together - it's Friday night, what better car to go cruising with (of course, the wife'll have to yell "honk" out of the T-Tops if needed!)
Anyway, I'm going to order those manuals and hold off until I get them. I'm going to assume the factory alarm isn't working since the horns are apparently dead.
Thanks for the help. Have a good weekend everyone!

Thanks Flemgunner -
I'll look there too. Maybe one of them is mounted there, with the other being the one I found behind the washer fluid. I figure that if your 75 has them in front, and 82collectorshark's 82 are also in front, my 78 is probably there too.

Ok, here we go:
I looked in front, and sure enough, there's two horns wired together. I would assume then that the horn unit I found behind the washer fluid is a horn for the factory alarm?
Now based on coincidences, I find it hard to believe that ALL three horns would be bad. With that in mind, I'm guessing maybe the horn/alarm relay might be bad. I did find a square blue relay with three prongs under the dash (driver's side). I also found a grey round harness with one wire, with no relay in place. Any guesses?

ok, new issue -
After taking the Vette to Ft. Myers tonight, the horns now work - not the alarm, but the regular horns. HOWEVER, the directionals now don't work! I replaced the flasher, and only the hazzards work. All the bulbs work, so I know it's not that. The fuse looks fine for the directionals, but I'll replace it anyway in the morning. If the fuse isn't the issue, I'll replace the directional arm (need a new end piece anyway). Am I on the right track with this?

Oh, and by the way, that blue square relay under the driver's dash was the horn relay - while doing an internet search for the alarm horn I stumbled apon it. Apparently, the replacements are now black.
When I had origianlly fournd the blue relay under my dash I re-seated it in the plug, and now the horns work. And thanks to a Sept. 2004 post by Gunslinger and "Lost in the 60's", I was able to fix the turn signal issue.
Now for the alarm horn issue. I know the power's getting to the horn, so I can safely assume the alarm relay is ok. Any idea where I can get a replacement alarm horn?
