Horn + general electrical questions

[posplayr]

Is that correct? It's a little hard to see the black terminal as it is under that other wire. But it looked right to me based on what I saw when I had the switch completely apart.

Any ideas??

Assuming the black wire is the same at the connector and follows the B/W into the harness you are OK. You can also put the black lead into the back of the connector, but do not open it else you will break the path.

see attached for test points on horn switch

 

[exzachtly1]

first as you already know the battery is in poor shape, but it might be even worse that you think without the horn, it is already dropping to 10.0V which is about 1.2V lower than it should (12.2-12.4v with key on is a healthy battery)

now there two measurements are interesting because if your are on the high side (of the horn), then you should be at the battery voltage and if you are on the low side you should be at ground (i.e. 0V). Anything else and there is resistance in the current path other than the horn.

With the 7.2V on the G/O see how much the battery is at; is it also at 7.2V or maybe a little higher? If he battery is still at 10V you have a huge resistance somewhere between the battery through to the ignition switch and fuse box back to the horn.

The 3.2V on the G is saying that your horn button is dirty and needs cleaning.

Thanks for your help, this is my first time messing with this stuff as you can probably tell. Before yesterday even my basic electrical knowledge was shaky at best... been learning a lot the past couple of days.

I'm going to pull the battery and take it for testing first thing tomorrow; if it's indeed bad then I will replace. I guess I'll be cleaning the button again too with some appropriate cleaner, but I swear it was super clean - I'll take pictures next time I have it apart.

I'll check the battery for resistance like you said - but will have to wait til tomorrow.

 

[exzachtly1]

Whelp, you were right - turns out my battery was totally junked. It failed right away on the CCA test, was only putting out like 86 CCA.

I splurged and bought a nice sealed AGM battery. Hooked it up, and immediately the horn works just fine. Nice strong, loud honk! Also the bike starts much easier and seems to idle better.

I checked the horn wires again and now getting around 11v at the wires. I skipped testing with the button depressed because I didn't want to annoy the neighbors too much and, well, it's working just fine.

Thanks for all the help, as usual.

 

[posplayr]

Whelp, you were right - turns out my battery was totally junked. It failed right away on the CCA test, was only putting out like 86 CCA.

I splurged and bought a nice sealed AGM battery. Hooked it up, and immediately the horn works just fine. Nice strong, loud honk! Also the bike starts much easier and seems to idle better.

I checked the horn wires again and now getting around 11v at the wires. I skipped testing with the button depressed because I didn't want to annoy the neighbors too much and, well, it's working just fine.

Thanks for all the help, as usual.

I looked at how a horn works, it is an electromagnetic voice coil that has a series switch that is activated (opened) once
The coil gets to maximum. So the coil must be relatively low resistance on par with the switch resistance. Your battery was so low that you could not get the series switch to open and so we see the voltages you measured.

 

[exzachtly1]

I looked at how a horn works, it is an electromagnetic voice coil that has a series switch that is activated (opened) once
The coil gets to maximum. So the coil must be relatively low resistance on par with the switch resistance. Your battery was so low that you could not get the series switch to open and so we see the voltages you measured.

Awesome, makes perfect sense. I'm glad that's all it was!