Headlights blinking on and off

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Had the Mustang out for short cruise today to lube it up since the sun was out; coming back it clouded up and I turned the headlights on and noticed the headlights were blinking on and off at about the same rate as turning signal although I didn't have my signals on. Anyone ever experience this and what's the possible fix?

Thanks!

Jim

 

midlife

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There are two possible problems, both related to excessive resistance in the circuit. The headlight switch contains a circuit breaker that can trip and re-set due to excessive current flow. This can be caused by poor connectors somewhere along the line. The usual suspect is the dimmer switch, which is notorious for breaking down causing this symptom. They are cheap and easy to replace.

If you have halogen or high intensity modern lamps, they draw more current than the old style lamps.

 

72 R Code

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I remember this happening to my Dad's Galaxy years ago. He just replaced the headlight switch as I recall.

 

Qcode351mach

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I remember this happening to my Dad's Galaxy years ago. He just replaced the headlight switch as I recall.
X 2 Headlamp switch

 

OLE PONY

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X3. Happened on my 73 too. New headlight switch fixed it.

 
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Start with the ground. Make sure the ground wires from the head lamps are clean and secure. They are small black wires coming from the housing, usually go to the front.

 

droptop73

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Start with the ground. Make sure the ground wires from the head lamps are clean and secure. They are small black wires coming from the housing, usually go to the front.
X2 before replacing the switch check the grounds, it's alot cheaper. BTW Midlife knows the wiring on early Mustangs as well as anyone, it would be good to follow his advice.

 
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Thanks for all the great information guys. I was going to check my grounds and connections today but when I turned the headlights on...they're no longer blinking??? I'm still going to clean the connections and checking them and if happens again I'll put a new switch on.

 
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Turns out it was the headlight switch. I found a youtube clip that was helpful in instructions on how to do remove the switch.


Note: One warning, to get the switch off you have push a small knob under the switch to release the rod used to turn the light on and off. Well mine was really frozen in there so I climbed up under the dash and while pushing the knob I gave it a really "hard" jerk and of course hit myself in right between the eyes when it did release, I saw stars for five minutes.

 

73vertproject

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Turns out it was the headlight switch. I found a youtube clip that was helpful in instructions on how to do remove the switch.

LOL! :rofl: Been there, done that!

 
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Born an I-6, spent the teenage, 20 and 30 years as a 302, but at 40 will reach full potential as a 351C.
FYI, a bad HI BEAM switch (foot switch) can prevent your headlights from turning on.

Not pertinent in this case, but when you are driving a car with 40 year old parts, all kinds of stupid things can happen.

I think I paid $10 at Autozone.

 

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