This is a non-air bag 740. I'm having an issue similar to this posted years ago here

http://www.brickboard.com/RWD/index.htm?id=735198&show_all=1

The horns themselves (under the bumper) are fine. They're getting 12V and grounding them would make the horn work fine and loud.

Next I removed the steering wheel and cleaned the horn contact ring, the little spring loaded connection. These 2 were coated with grease and grime. After doing this I measured 11.95V going INTO the steering wheel from the horn contact ring. For good measure, even though my horn contact switch (the flex copper plate with the nipple) are newish as I had them replaced a few months back, I opened up the horn buttons and cleaned everything up.

After all this work, from no horn at all I'm now getting a tiny (pathetic) beep from the horns, not the typical commanding volvo horn sound.

I suspect the ground needs to be cleaned where question is where is the ground? Is the steering wheel grounded to the steering column / shaft? I can see no other pathway.

Thanks