Problem with dual electric horns

72GT160

Petty Officer 2nd Class
Joined
Apr 22, 2007
Messages
106
I purchased new horns as old didn't work. I have two sets of wires going to horns. They don't work when both are wired up. Each will work if wired only to one. I have power to both leads. When both are wired I just get a clicking sound. Thought that maybe the 5amp fuse for switch was maybe the cause but, put larger fuse in temporarily and that did not work. I also, wired to a jump pack and both horns will sound.

So, what's the problem?
 

GA_Boater

Honorary Moderator Emeritus
Joined
May 24, 2011
Messages
49,038
Compare the voltage when one horn is connected and when both are hooked up. Also see what the voltage is when you aren't trying to blow the horn. All three should be over 12 volts, a little less when the horns are blowing or trying to blow.

What is the battery voltage and is the power to the horns the same on both sides of the horn switch/button? Check the power feed and ground connections corrosion and tightness, starting at the battery.
 

gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,585
Sound to me like you have then connected in series and not parallel. And when you have both connected, there are only seeing 6 volts each which is not enough to make them work and hence the clicking noise. Horns work basically the exact same way as buzzers do. but they have apertures to make the sound resonate louder. Otherwise they are the same. And since the horns are 12 volt setups, each one has to be wire in a parallel fashion to work. JMHO!
 

Grandad

Lieutenant Commander
Joined
Jun 7, 2011
Messages
1,504
I agree with GA. Low voltage is likely your problem caused by corrosion/poor contact, weak battery or a combination of those. - Grandad
 

72GT160

Petty Officer 2nd Class
Joined
Apr 22, 2007
Messages
106
Ok, so I've got 14.71v +/- at each wire not connected, button pressed. Hooked up to horns and when button pressed I have 4.5 - 4.7v at both terminals. Wires at switch/button are purity buried but, I can see only on lead wire coming off terminal, with no other possible leads that come off it. Battery connections great, no corrosion to see at button.
 
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72GT160

Petty Officer 2nd Class
Joined
Apr 22, 2007
Messages
106
Further testing, I connected only on horn and tested both leads while pressing button. Both had 9.6 - 10 v. And that one one horn was sounding.
 

gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,585
Further testing, I connected only on horn and tested both leads while pressing button. Both had 9.6 - 10 v. And that one one horn was sounding.

That doesn't sound right. If the battery is supplying the proper current, you should be reading the exact same voltage at the horn with the button pressed or very close to it, that you are reading at the battery. So I think you have something zapping the current. And that does sound like either terminal connections or wiring.
 
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