Would this horn fit?

Disc Horn Volume Adjustment Screw?

I went out to my car and tried to adjust the disc horn on the driver's side (actually it's about dead center).

I removed the disc horn from its bracket because I didn't see any screw on the front side of the disc.

On the backside of the disc horn was a little, unpainted, philips screw which I tightened clockwise with a tiny screwdriver. I'm not sure I tightened it as much as I could.

In any event, I think it worked. The horn seems louder. But I wouldn't say that it jumped from 50db to 100db.

Ray -- below is a picture of the backside of the disc horn showing that little philips screw on the right. Can you confirm that this is the screw to turn?

Thanks.

 

Yes, the little silver philips screw on the right. It's the only screw on the disc horn as far as I could tell. (Unless it's that big philips screw in the center; but I don't think so as that looks like a mounting screw.)

It's a tight squeeze in there if you're only going to remove the black plastic cover. Be careful. You can easily lose a nut, a screw, a washer, a tool, or drop the horn.

I think I would like to do it over and also do the passenger side disc horn. But I would really prefer to have Ray first tell us that I got the right adjustment screw.

 

Boy is my face red. When I adjusted mine (without removing it from the car frame), it was definitely louder, but today I finally tested it while driving and it is louder but like Boo said not as loud as I claimed when my head was near it.

From your pix Boo it should be the phillips on the right with paint around it to prevent it from turning, used as locktite.

Anyway the screw is off center and on the outer ring about 1/4 to 1/2 inch from the edge. I would take a pix but I don't think I need to since Boo already has one.

By the way, don't just screw it in or CW you should be able to back it out also CCW, if it works like others that I have played with you can change tone and volume.

Let me say this so that there isn't any confusion regarding playing with the adjustment - It may become louder either way, CW or CCW. You should experiment and not do like I did when I just blew the horn once before and once after.

I may have to go back in at another time and see if I can get it even better, just don't unscrew it all the way out or you will be taking it apart to fix it.

It is built just like a speaker only using different materials to cause the louder clang. You usually have two, one for highs and one for lows freq, they are normally the same horn but they have been adjusted for the difference with this screw. Hell put in a door bell, it's about the same thing. lol

No warranties come with this job, and the tech has packed his bags and left for parts unknown.

 

Thanks Ray! Good to know that I identified the right screw!

When I go out again for a do-over and to do the passenger side horn, I'll experiment with the clockwise versus counter-clockwise turns you mentioned.

BTW, I do think that my tightening it clockwise did make it louder. Just not quite as loud as what I imagined a jump from 50 to 100 db would be.

Thanks again for the tip!

 

Interesting idea that the horn volume can be increased. But one reason I upgraded was to get the two-tone horn. To me it sounds a lot classier. The OEM Prius horn puts me in mind of my 1966 VW. Even it it's louder, I'm still not fond of the squawk sound. But for those who don't mind the sound, increasing the volume sounds like a welcome idea.

 

Yes, I know what you and Ray mean.

FYI, what I think I noticed from tightening the adjustment screw to the degree that I did on the driver side horn, was both an increase in volume and a lowering of the pitch.

But I'm going to experiment with it the next time I get out there. Now that I've done it once (and know better how to unscrew and screw back the different type screws), it should be easier the second time and easy to experiment.