The horn on my 2011 Nissan Cube no longer works. Since it has never been a good horn (it's too soft), I figured that it would be good to replace it anyway.
I have tested that the horn relay clicks when I press the horn button on the steering wheel, and I have used my multimeter to verify that the 10amp horn fuse is still good.
I removed the horn from behind the bumper and used my multimeter to verify that the spade connectors for the horn are receiving 12 volts when I press the horn button.
However, when I hooked up the new horn and wanted to test it before I close everything up, it also doesn't work!
I used my jump pack (JNC660) and some test leads to make sure the new horn was not defective, and it worked properly. Then I used the jump pack to test the old horn, and it also worked!
If I have tested that the horn switch, horn relay, horn fuse, and horn are all working, and that the horn terminals have 12v when energized, why does the horn not sound? What else can I check?
(Note: I have the service manual, and it does not have any useful information. The wiring diagrams verify that everything I have tested is correct, and there are no instructions other than for physical removal/replacement.)