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Old 10-13-2020, 07:25 PM   #1
Standing Elk
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Default Question on power to the light / horn switch

Is there only one hot wire that supplies power to the light switch and horn? My lights have gotten a little dim and my horn is not working correctly. Car starts fine and the battery is staying charged just fine. Am wondering if maybe there is an issue with the wire / wires that bring power to the switch on the bottom of the steering column. Thanks
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Old 10-13-2020, 08:46 PM   #2
GRutter
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Default Re: Question on power to the light / horn switch

Lights and Horn are powered slightly differently.

Lights are powered from the light switch at the bottom of the steering column, and are grounded at the lamp.

The horn is powered directly, and is grounded via the center contact on the light switch, up through the steering column, at the horn button.

Both lights and horn, however, are connected to the generator cutout terminal as their "source"

If both lights and horn are struggling check your battery connections, especially the ground strap. Check the connections at the starter switch, terminal box, ammeter, and at the generator cutout.

Look at this wiring diagram and follow it along
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Old 10-14-2020, 07:34 AM   #3
Joe K
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Default Re: Question on power to the light / horn switch

And check your ground from the headlight bar to the frame. The normal path for grounding is all done with likely "fresh painted" connections, i.e. probably a "challenged" connection.

Many restorers after laboriously making sure everything is painted for preservation find issues with various ground paths throughout the vehicle. Starter is another one of these.

It may be worth your while to run ANOTHER ground from say the headlamp reflector shells and horn motor field bolts down to the frame of the car.

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Old 10-14-2020, 08:37 AM   #4
Badpuppy
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Default Re: Question on power to the light / horn switch

I ran a ground wire between the light conduit to the forward hood latch screw on each side. Attach tinned wire end to conduit with a hose clamp, #10 lug on the frame. Eliminates problematic connections through bar and fenders. I added a horn relay and ran its ground wire through the horn conduit to the same point on the frame.
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Old 10-14-2020, 08:46 AM   #5
Kurt in NJ
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Default Re: Question on power to the light / horn switch

There should be 2 wires going from cutout to light switch, one for lighting, one for horn---
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Old 10-14-2020, 10:09 AM   #6
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Default Re: Question on power to the light / horn switch

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Quote:
Originally Posted by Kurt in NJ View Post
There should be 2 wires going from cutout to light switch, one for lighting, one for horn---
My '30 CCPU has two wires from the cutout - one to the horn, one to the terminal block. Nothing to the light switch. Everything works, though. This seems to be a commercial wiring harness.


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Old 10-14-2020, 10:40 AM   #7
ryanheacox
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Default Re: Question on power to the light / horn switch

You might have the same harness as me. I have one black wire that feeds the lights and horn off the generator. It must be spliced into the horn and light switch feed wires in the main loom. Can't think of any other way it would be done.
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Old 10-14-2020, 01:58 PM   #8
Ruth
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Default Re: Question on power to the light / horn switch

Quote:
Originally Posted by Kurt in NJ View Post
There should be 2 wires going from cutout to light switch, one for lighting, one for horn---
3 wires from cutout, one to light switch for lighting, one to horn first then to horn button via the light switch. third wire to junction box.

Quote:
Originally Posted by JayJay View Post
My '30 CCPU has two wires from the cutout - one to the horn, one to the terminal block. Nothing to the light switch. Everything works, though. This seems to be a commercial wiring harness.

JayJay
I'm curious, where does the pwer to the lights come from?
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Last edited by Ruth; 10-14-2020 at 02:09 PM.
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Old 10-15-2020, 10:02 AM   #9
Standing Elk
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Default Re: Question on power to the light / horn switch

Thanks everyone. I found a cobbled job inside my horn. The wires were just stuffed into the connectors. I have installed new connectors and mounting blocks in the horn and am waiting on some new ends for the two horn wires. I also took my light switch apart and cleaned it with electric contact cleaner. This seemed to help the light some. I will experiment with an additional ground wire to see if that helps even further. Thanks again
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