headlights flashing

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Feb 9, 2014 | 11:44 AM

karjunkie

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From: Lexington. Mi.

headlights flashing

hey fellas, I have a 74 250 4 by 4 with the 390and after a short while my headlight start flashing sometimes will stay on for a while sometimes they wont, anybody ever have this problem before

Feb 9, 2014 | 11:48 AM

tbear853

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From: The Shenandoah Valley

Seems to me I had that happen on a car I used to own many years ago, was either a headlight relay .... or a circuit breaker?

Feb 9, 2014 | 12:11 PM

fmc400

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Joined: Apr 2004

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From: Austin, TX

No headlight relay on these trucks. There's a circuit breaker built in to the headlight switch. Check for shorted, pinched wiring or frayed insulation downstream. An overcurrent condition is causing the breaker to interrupt.

Feb 9, 2014 | 12:24 PM

karjunkie

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From: Lexington. Mi.

are you talking about before or after the headlight switch

Quote:

Originally Posted by fmc400

Feb 9, 2014 | 12:25 PM

fmc400

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From: Austin, TX

Downstream means after the source, toward the load. So, "after."

Feb 9, 2014 | 12:48 PM

User 71024

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I've had problems with the OEM switches not being capable of handling Halogen bulbs. But I can't remember what year they started using halogens. In those cases we wired a relay for high and another for low beams and solved the problem. I'm guessing by now they are making the headlight switches to handle the amps, so if it is just a weak breaker in the head light switch a new switch should probably fix it. Unplug one of your headlights and see if they stay on twice as long, that will tell you the switch is weak.