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Headlight flickering

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Old May 13, 2013 | 10:18 PM
  #1  
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Headlight flickering

Hey guys i have yet another problem. Its only happened 1 time before this so ive never worried about it much.

So im working on my offroad lights on my 71 so i have all my lights on. Its hooked up to a battery charger so my battery wont drain.
My lights have been on for about 20 minutes now and just the headlights started flashing on and off. Not my running lights tirn signals or anything. Justthe headlights (and cablights that are wired to the headlights.) i tried shutting my lights off for a few then back on. That fixed it for 10 or so minutes then they started flickering again

Any ideas what this is guys? When this truck is back on the road i will be doing quite a bit of night driving (home from work) so id rather not have this happen again while driving.
Any help is appriciated.
 
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Old May 13, 2013 | 10:29 PM
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is the switch over heating?
 
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Old May 13, 2013 | 10:56 PM
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Not that i know of. The last time this happened i was only driving with the lights on for 3 or 4 minutes. What would cause it to overheat?
 
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Old May 13, 2013 | 11:33 PM
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It sounds to me like the circuit breaker is tripping. It will turn the headlights on and off repeatedly. Did you power your off road lights from the headlight circuit?
 
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Old May 13, 2013 | 11:56 PM
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Well the lights arent hooked up now. I was bolting them in and geting wirin layed. I had the lights on so they would reflect onthe camper infront of the truck. It gave me that extra little bit of light.
 
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Old May 14, 2013 | 03:54 AM
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A resistor in the light circuit is breaking down. A known issue for a long time. I resolved it by doing the Whiter, Brighter light upgrade found in the article section on this site. The old wire is cut to the headlight, a relay is added and a new hot wire feeds the lights behind the relay relieving draw on the system, while burning the headlamps brighter.

Dirt & rust around the dimmer switch is another area to look at and clean.

guluk


John
 
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Old May 14, 2013 | 09:55 AM
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I, had a camper on for many yrs with all the over head light about 12+ lights or so on it. Then one night on a lonely dark road my lights started going off & on. I had to stop as they were staying off more then on. I fixed it weeks later as it was the wiring harness plug that connects that runs along the inner fender well. Cleaned dirty contacts then applied electrical grease still working good today 20 yrs ago. Then 2009 heading out early morning to my son's home to the Las Vegas area my lights started flickering after about 15 minutes on the road so turned on my off road lights until, I could stop at a safe place that had some lighting. Once stopped, I could hear the light switch clicking every time the lights went off..Ok Fast forward. I replaced the old switch with a new one and never had any more problems, not even with a 3g 130 amp Alternator upgrade.. my 2cents....orich
 
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Old May 14, 2013 | 11:28 AM
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The circuit breaker is in the headlight switch. It's rare for them to go bad on their own but it's not impossible. You could have a bad connection somewhere or even a short. If you've replaced your standard "sealed beams" with some type of high wattage halogen headlamps your circuit breaker will cycle "on" and "off" because the headlight switch and circuit is overloaded. High wattage halogens (bulbs over 65 watts) need the headlight relays mentioned above.
 
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Old May 14, 2013 | 11:38 AM
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Old Jun 2, 2013 | 10:40 PM
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Ok sorry guys. Havent had internet for a bit. So coul it be that i have to much power going trough my headlights? I have them hooked up to my cab lights and clerence lights (11 lights in all) so maybe i have to muc power going trough them. Also i got some cheap halogen lights from autozone. I dont remember what wattage but im sure it was over 65.

Whats the best way to solve this? The whiter whites upgrade?

Thanks all
 
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Old Jun 2, 2013 | 10:52 PM
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Originally Posted by lilsmokey
Ok sorry guys. Havent had internet for a bit. So coul it be that i have to much power going trough my headlights? I have them hooked up to my cab lights and clerence lights (11 lights in all) so maybe i have to muc power going trough them. Also i got some cheap halogen lights from autozone. I dont remember what wattage but im sure it was over 65.

Whats the best way to solve this? The whiter whites upgrade?

Thanks all
The best way to solve the issues is to install relays to bypass the headlight switch and only use the headlight "On" position as a signal to energize the relays and connect the headlights directly to battery voltage. The result is brighter lights and less load through the headlight switch.

Basic Electricity Lesson:
Power (Watts) is a function of current X voltage or P=(I x E). Solving for I for example, it's 65 Watts divided by 12 VDC = 5.4 amps (current) each headlight draws. Add up the total Watts of the clearance lights and the cab lights and yer running out of amps through the fuse. Therefore, the more current it is consuming (and summarily higher total Watts), the more heat that the headlight switch is generating. Hence prolly why your headlights are cycling.
 

Last edited by HIO Silver; Jun 3, 2013 at 09:30 AM. Reason: Deleted reference "whiter whites" cuz it ain't a headlight bulb.
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Old Jun 3, 2013 | 05:36 AM
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lilsmokey Have you looked at or read the Whiter light upgrade article, it is plain that HIO Silver has not. Adding relays is what it's about.



John
 
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Old Jun 3, 2013 | 08:28 AM
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Do the relay mod.

The stock writing is really inadequate for even the OEM lights. It's literally like night and day difference in light output and very easy to do.
 
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Old Jun 3, 2013 | 09:28 AM
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Originally Posted by jowilker
lilsmokey Have you looked at or read the Whiter light upgrade article, it is plain that HIO Silver has not. Adding relays is what it's about.

John
Aha, thanks John. 'assumed it was some sorta aftermarket headlight bulb.
 
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Old Jun 3, 2013 | 12:30 PM
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Similiar light problem

I am trying to get the 69 back on the road again and was checking all lights/bulbs.I can make the headlights and park lights burn for about 10-15 seconds and then they will all go out.Turn the hl switch off And back on and they will burn for the same amount of time and go off.
From reading the above posts,what is the next step to getting these fixed?Headlight switch or mods?
 
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