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Horn/Hazzard Electrical Problem

gpeplau

Newbie
Joined
Sep 14, 2015
Messages
30
Hey all,

TLDR: Having a problem with my horn shorting somewhere with the hazard switch(even when hazards are off) causing the horn to go off like a vehicle alarm.

Long version: I have a 1975 Ford Bronco that I installed a new full American AutoWire wiring harness on in the beginning of this year. The wiring harness was installed by myself, an electrical novice, but had no issues when testing it. All components worked as they should for months; horn, engine spark, lights, hazards, etc. The problem that I am having now is that every time I connect the battery terminals the horns go off like car alarm. The horns seem to be linking somewhere to the hazard unit or flasher cans. If I pull the fuse for the hazards, the horns will stop going on and off. The wiring harness for the steering column is also new from Tom's. This problem happened only once before and I simply disconnected the battery terminals and re-connected them and the problem ceased. Now it is going on full time when the batter terminals are connected. What could it be? Should I replace the flasher cans? Any help or insight would be appreciated. Thank you!
 

Viperwolf1

Contributor
electron whisperer
Joined
Aug 23, 2007
Messages
24,143
Unplug the column connector and see if it still happens. I suspect that will narrow the problem to somewhere in the column.

Make sure you have the wires in the correct spots at the connector.
 

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EricLar80

Bronco Guru
Joined
Jun 14, 2001
Messages
2,170
Check the copper horn ring to see if the ring has a bridge between the two sections.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
43,999
Well in theory at least, there should be only one trace/ring for this year bronco. It’s got the relay from the factory.
But with the new harness things would’ve changed in this regard.
It’s also very easy to get horns connected incorrectly with a new harness.
 
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gpeplau

Newbie
Joined
Sep 14, 2015
Messages
30
If it were wired incorrectly, wouldn't this problem have persisted from the beginning, not 6 months later?
Viperwolf1, thats a good idea to isolate the harness in the steering column. I will do that this week and update.
EricLar80, thank you. I will check the ring. That is a good idea.
 
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gpeplau

Newbie
Joined
Sep 14, 2015
Messages
30
Update:
I disconnected the column harness from the main harness as well as verified that everything was wired correctly and the problem persisted. Since I was able to narrow the problem to the main harness, I started to un-loom the harness and I found a couple of exposed wires. I do not know how they would have gotten exposed, but one of them was the horn relay and some others. Repaired the wires and the problem is taken care of. As always, thank you all for you assistance!
 
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