Posted by Keith in Washington [24.41.55.59] on Wednesday, April 03, 2013 at 11:46:18 :
In Reply to: Re: Wiring Horn? Pic Included! posted by Keith in Washington [24.41.55.59] on Wednesday, April 03, 2013 at 11:25:03 :
Use a volt meter first to make sure that you have voltage to the one wire coming to the horn. One wire should have 12 volts and the other will be open no voltage and not grounded. The open wire goes into the end of the steering column and up to the horn button. Press the horn button and the open wire will then be grounded.
The adjustment screw adjusts a set of contacts in the horn. When you push the horn button the diaphragm moves in one direction due to current running through the wire coil in the horn. When it has moved so far it mechanically opens the contacts and shut off the current and the diaphragm moves back towards its original position but as it moves back it closes the contacts and the diaphragm plunges forward again only to break the contact again. It will repeat this until the horn button is released and there is no current running through the coil.
The set screw adjusts the position where the diaphragm opens the contacts. If it is adjusted so that the contacts never open the diaphragm will move forward and stay until the horn is released (you should hear a single small thunk when you push the horn button). If it is adjusted so that the contacts are not closed in the "rest" position no current ever flows the diaphragm will never move and therefore no sound. You need to find the adjustment position between these two points.
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