E230 1996 horn not working
 

The horn is not working
Checked the horn with 12volt direct and works.
Have checked the horn leads and no voltage present when horn is pressed.
Checked fuse under rear seat and is ok
All I can hear is a relay click under bonnet
Any help greatly appreciated.

It is sometimes possible for the fuse to develop a hairline crack and thus not pass current while it otherwise visually apears to be good. If you know the horn is good and the relay is clicking, try putting in a new fuse anyway to see if it makes a difference.

The horns on my w123 on occasion tend to fill up with dirty water and they stop working. I shook out most of the water and got it to make a faint beeping sound. After about five minutes in a toaster over (until steam stopped coming out) I took it out, let it cool, and it worked once more.

A fine horn from a luxury car at a junkyard cannot cost more than $5.00. A new horn at any autoparts store costs about $15.00.

12v is 12v. A relay should not make any difference.

Horn Not working
 

Thanks Guys for the responses
Will try over the weekend