Well, you just access the circuit and test, starting at the horn.
Two terminals. One has power on it ( all the time I think too, not just with
the key on, but full time )  ...you check for 12 volts there.
If it's not there, work on that.
If it's there, you ground the other terminal- that should make the horn
work.
If it doesn't you figure the horn is dead, then remove it and try to operate
it on just a battery by itself.
If the horn works, then you work on why the rest of the circuit isn't
supplying ground when you push on the horn button.  
Check your horn contact ring on the underside of the steering wheel, and
check the piece that rubs on it.  There is such a thing as an 'open steering
wheel' too I think, that won't conduct for the horn function.
It's an odd circuit and trickier to troubleshoot than a tall light say.
Scott

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
most david
Sent: Friday, December 21, 2007 1:58 PM
To: vanagon@GERRY.VANAGON.COM
Subject: horn not working after replacing ignition switch?

I replaced the ignition swith in my '87 this summer (to attempt to fix a
problem that it didn't fix, but that's another story).  The new ignition
switch and all else is working fine now.

But, the horn has not worked since replacing the switch.  I've double
checked the connections (spade connectors?) at the steering wheel.  The
assembly after installing the new switch went fine according to the great
instructions on a couple of vanagon web sites.  I've also checked the
appropriate fuses, and they're fine.

So, any ideas where I might look to get the horn working again?

Thanks for the help.

David
'87 GL Camper

 
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