For some reason, the volume of my dual-tone horn on my SL is quite low. Not sure why or what to do about it. The horns both emit their tones but the volume is too low to be effective.

 

Hello and welcome to the forum? Which SL platform is this in regards to? If it is for the R107, please take a look at the link below on the procedure to address the issue. Please let us know if you have any questions.

Mercedes-Benz R107 Horn Replacement | 1972-1986 - 450SL, 380SL, 500SL, 560SL | Pelican Parts DIY Maintenance Article