3 prong headlights and dimmer switch question
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Elder User
Joined: Feb 2003
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From: Winnipeg Canada
3 prong headlights and dimmer switch question
Need help with my head lights, how do they work exactly? They are 3 prong, ground, hi and low beam. When they are on low beam, does 12 volts go into one prong, then on hi beam there is 12 volts going to the other prong. So there would be 24 volts total going through the light? also, the dimmer switch, does it act like a N/O N/C switch?
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Elder User
Joined: Feb 2003
Posts: 850
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From: Winnipeg Canada
Well here's my problem, I hooked up the headlights, driver side works fine, passenger side is very dim, with headlights on, you get 12 volts on driver side, 4 volts on passenger, take the headlights out, you get 12 volts on all contacts. If you have the driver side headlight out and the passenger side in, it doesnt even work at all! Whats going on??
Senior User
Joined: Mar 2002
Posts: 244
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From: Blenheim, Ontario, Canada
I believe that you have corrosion or wire breakage somewhere between left and right headlight, likely at the left headlight connection. The left headlight installed improves the connection a little. With no current flowing, you might see 12 volts everywhere but as soon as the current flows, the resistance offered by the poor connection, limits current flow and hence the low voltage at the right headlight. Again, I would look at the wiring connections at the left headlight connection particularly the wire coming from this connection over to the right headlight.
just my thoughts.
Regards, John
just my thoughts.
Regards, John
Elder User
Joined: Apr 2004
Posts: 545
Likes: 1
From: Shreveport, La.
Ditto on PJS55. Check for frayed wires, loose connections, etc. all the way back to the switch in the cab as well as dimmer switch. Any slip or terminal type connection would probably benefit from cleaning and re-assembly with dielectric grease.
Inner workings of the dimmer switch is also a possible culprit.
The headlights themselves, are the terminals tight on them? If you can detect any looseness, discard and replace.
Inner workings of the dimmer switch is also a possible culprit.
The headlights themselves, are the terminals tight on them? If you can detect any looseness, discard and replace.
Lead Driver
Joined: Apr 2002
Posts: 8,813
Likes: 13
From: Littleton, New Hampshire
Originally Posted by pootscratch
In some cases, dim lights means poor grounding. Check any ground wires that you might have....maybe something is loose, or corroded and not making proper contact.
Vern
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Logistics Pro
Joined: Oct 2002
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From: Valley Center, CA
Ditto on the above suggestions. Before you start taking things apart though, I would have somebody watch the brightness of the light while you wiggle the wire progressively back to the switch. It may flicker showing you where the bad spot is. Good luck, John 
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Elder User
Joined: Feb 2003
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From: Winnipeg Canada
Well I got home from work and went straight to tinkering with it. I'd get 5 ohms or so then turn on the light, check resistance again and it'd shoot up to 5 MEGA ohms :|
So I put the ground to another screw on the headlight bucket and voila, it works.
The stupidest things agrevate me the most! :@
So I put the ground to another screw on the headlight bucket and voila, it works.
The stupidest things agrevate me the most! :@
Thread Starter
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Elder User
Joined: Feb 2003
Posts: 850
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From: Winnipeg Canada
Originally Posted by GreatNorthWoods
Grounding problems can cause some weird symptoms. Try working with an all fiberglass car or one with a wood dash sometime.... 
Vern
Vern
The instructions on the Ron Francis kit says the exact same thing in bold
Postmaster
Joined: Jan 2003
Posts: 4,417
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From: Durham, NC
Originally Posted by joners
Well I got home from work and went straight to tinkering with it. I'd get 5 ohms or so then turn on the light, check resistance again and it'd shoot up to 5 MEGA ohms :|
So I put the ground to another screw on the headlight bucket and voila, it works.
The stupidest things agrevate me the most! :@
So I put the ground to another screw on the headlight bucket and voila, it works.
The stupidest things agrevate me the most! :@
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1954, car, connection, dimmer, f100, flickers, ford, headlight, navigation, prong, pronged, switch, switsch, utlimaster, wires
