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1982 kz440a
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Discussion Starter · #1 ·
12.7 volts at battery. 11.7 volts at horn terminals (when switch is depressed) two verified working horns (when jumpered directly from battery) why no horn!!??? (Can we please ignore the fact that there is a 1v drop... and also don't say the horn is chassis ground because it has 2 terminals and it works on the bench regardless of polarity....)
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1982 kz440a
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Discussion Starter · #2 ·
Oh no! I guess horns actually require a good deal of current. (Hence good meter readings but no dice under load. .) The ground to the hand controls must be inadequate... but how!? There are two! (When ground jumpered directly to hand control housing (or horn switch chassis it works as desired)
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Discussion Starter · #5 ·
This is fucking weird. Not voltage drop all the way through the loom. Actually no voltage drop at all now but when I measure from battery positive to control chassis I get 12.7v then when I depress the switch it drops to .5v wtf does that mean? There should be no change in voltage when I press the button. The switch doesn't break a circuit its just supposed to ground the horn!
 

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Lol... is anybody laughing at me and my black handlebars yet? Its dark now. I'm gonna feel pretty stupid if that's the problem...
Sure could be the bars...............really could be the bars if they are painted.......not anodized black. When the sun comes up run a jumper from the ground side of the switch to GOOD & KNOWN ground to make sure the switch does work and make sure you decon the switch before putting it back together
 

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You can switch your test meter to a low resistance setting and measure the resistance through the wire connections to the battery ground a little easier then measuring voltage drops on the loads, handlebars rarely provide a good ground because even if they are not rubber mounted at the yoke, the only fork to chassis metallic ground connection is through the steering head bearing. This is the reason all motorcycles have so many ground connection wires to begin with, your most reliable fix is to simply add an additional grounding wire to the switch mount.
 

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Unfortunately, horns are usually wired power-> horn->switch and ground through the switch so it's imortant to have a good ground. You could add a wire from the switch ground to a known good chassis ground.
 

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Unfortunately, horns are usually wired power-> horn->switch and ground through the switch so it's imortant to have a good ground. You could add a wire from the switch ground to a known good chassis ground.
TR, You were with us at that party after the race where that Davidson fellow won and his buddy Harley paid for the first round, right ? You remember that was just before we got involved in that stupid war in Europe. Reminded me of those flying things......calling them aeroplanes............they'll never catch on.
Cheers Mate
 

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TR, You were with us at that party after the race where that Davidson fellow won and his buddy Harley paid for the first round, right ? You remember that was just before we got involved in that stupid war in Europe. Reminded me of those flying things......calling them aeroplanes............they'll never catch on.
Cheers Mate
wrong century, I'm a boomer
 
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