Horn Circuit Refurb
Thread Starter
Le Mans Master
Joined: Jun 2002
Posts: 8,339
Likes: 24
From: I can walk to MA
Horn Circuit Refurb
Another bump in the road to getting an inspection sticker ...
Yeah - it's pretty simple to do.
Here is what I found in my 75 circuit.
1 - horns not working.
2 - Haynes manual says to replace relay (that's all it says)
3 - find relay and discover it is bad (thanks to year-specific AIM)
4 - fix relay (most people would replace this)
5 - discover intermittent horn button
6 - clean up horn button and reinstall
7 - Beep Beep
Pics:
It varies from year to year, but the horn relay is near the fusebox for 75s:
http://NHvette.com/ftp/in/75_horn_relay_loc.jpg
Here is what mine looked like when I opened her up.
The contacts were corroded to hell and the steel piece
that the electromagnet attracts had rusted off.
http://NHvette.com/ftp/in/75_horn_relay_01.jpg
I cleaned it up best I could and glued two small washers in place
of the steel part that rusted off.
http://NHvette.com/ftp/in/75_horn_relay_02.jpg
After cleaning the contacts, the spacing has to be tweaked
just right to work properly. To far apart and the relay will
switch on/off/on/off/on/off by itself. If too close, then the
contacts will close when bumped - setting the horn off when
you drive over anything not smooth.
With the relay working, my horn button turned out to be intermittent.
Here it is removed and taken apart (three nylon push-in rivets).
This picture shows it after cleaning with fine sandpaper.
http://NHvette.com/ftp/in/75_horn_button_01.jpg
To be sure it keeps from rusting up again, I painted all
the pieces with silver conductive paint.
http://NHvette.com/ftp/in/75_horn_button_02.jpg
After install, it works perfectly.
http://NHvette.com/ftp/in/75_horn_button_03.jpg
I'm installing two new 138db "magnum blaster" horns.
They aren't too much louder than stock, so I think I might
keep one or both stock horns also. That, or buy two more MB horns.
Yeah - it's pretty simple to do.
Here is what I found in my 75 circuit.
1 - horns not working.
2 - Haynes manual says to replace relay (that's all it says)
3 - find relay and discover it is bad (thanks to year-specific AIM)
4 - fix relay (most people would replace this)
5 - discover intermittent horn button
6 - clean up horn button and reinstall
7 - Beep Beep
Pics:
It varies from year to year, but the horn relay is near the fusebox for 75s:
http://NHvette.com/ftp/in/75_horn_relay_loc.jpg
Here is what mine looked like when I opened her up.
The contacts were corroded to hell and the steel piece
that the electromagnet attracts had rusted off.
http://NHvette.com/ftp/in/75_horn_relay_01.jpg
I cleaned it up best I could and glued two small washers in place
of the steel part that rusted off.
http://NHvette.com/ftp/in/75_horn_relay_02.jpg
After cleaning the contacts, the spacing has to be tweaked
just right to work properly. To far apart and the relay will
switch on/off/on/off/on/off by itself. If too close, then the
contacts will close when bumped - setting the horn off when
you drive over anything not smooth.
With the relay working, my horn button turned out to be intermittent.
Here it is removed and taken apart (three nylon push-in rivets).
This picture shows it after cleaning with fine sandpaper.
http://NHvette.com/ftp/in/75_horn_button_01.jpg
To be sure it keeps from rusting up again, I painted all
the pieces with silver conductive paint.
http://NHvette.com/ftp/in/75_horn_button_02.jpg
After install, it works perfectly.
http://NHvette.com/ftp/in/75_horn_button_03.jpg
I'm installing two new 138db "magnum blaster" horns.
They aren't too much louder than stock, so I think I might
keep one or both stock horns also. That, or buy two more MB horns.
