Headlights flashing

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wildcard
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Headlights flashing

Post by wildcard »

My headlights went out about a month ago and flashed on & off a few times. I pulled over and shut the lights off for a minute. Turned them back on and drove the rest of the way to work on dim. I'm thinking dimmer switch, so I replaced it that evening. Everything was fine for a week or so and then they go out again. Since then, I installed a set of driving lights in case it happened again.
This morning on the way to the lake, they start flashing again. Driving lights saved me a trip to the ditch since I was on a narrow county road. :eek:
Am I wrong about the dimmer switch being bad? Or would a bad light switch cause the flashing too? I always heard the dimmer switch would make them flash and the light switch would make them go out and stay out. :?
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chad67
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Re: Headlights flashing

Post by chad67 »

There was recently a post about this. The switch on these trucks routinely go bad and cause this. I believe they have a thermal overload circuit beaker in them that wears out. Get a NEW switch and your problem should be fixed.
1967 F100 SWB
1991 Thunderbird 5.0 with fully ported gt40 heads, cobra intake (also ported) and a trickflow stage 2 cam, manual steering, and custom 3" exhaust
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HIO Silver
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Re: Headlights flashing

Post by HIO Silver »

Or better yet make or buy a headlight relay wiring harness and use the signal voltage from the headlight switch to energize the relays which sources voltage directly from the battery. The result is brighter headlights and yer headlight switch will last longer. Unless ya get an NOS switch, the new one will likely be imported and made of lesser quality. LMC offers a harness for about $30. You can fab up your own for as little as $10.

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