Author Topic: Headlights dim and pulse - 68  (Read 209 times)

Offline 68 GT

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Headlights dim and pulse - 68
« on: November 18, 2024, 03:54:19 PM »
The headlights on my 68 coupe are not very bright and they kinda pulse brighter to dimmer while driving at night. I believe they do this no matter if I have them dimmed or not dimmed with my dimmer push button foot switch. I believe my blower motor also speeds up and slows down a bit when I have the blower on high. Has anyone else experienced these problems? What headlights are people using in their 68 Mustangs?

Thank you for any advice and guidance.
« Last Edit: November 18, 2024, 05:17:09 PM by J_Speegle »
VIN 7T01C246XXX
Actual build date 5-11-67

VIN 8F01J208XXX
Actual build date 6-27-68

Offline ruppstang

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Headlights dim and pulse - 68
« Reply #1 on: November 18, 2024, 04:36:51 PM »
It sounds like a voltage regulator problem. The originals used points, and they could cause the pulsing. New ones are solid state and are less problematic. To keep the original appearance, you can move the old cap to the new one.
On a driven car I have used Halogen headlights. If you use them, it is best to replace the headlight switch as they draw more current.
« Last Edit: November 18, 2024, 05:17:24 PM by J_Speegle »

Offline midlife

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Re: Headlights dim and pulse - 68
« Reply #2 on: November 18, 2024, 09:12:15 PM »
It sounds like a voltage regulator problem. The originals used points, and they could cause the pulsing. New ones are solid state and are less problematic. To keep the original appearance, you can move the old cap to the new one.
On a driven car I have used Halogen headlights. If you use them, it is best to replace the headlight switch as they draw more current.
If using halogen headlights, best to run them off a relay system, as any of the stock headlight switches can't handle the power that halogen lamps draw.  Lots of kits out there for headlight relays.
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Offline 68 GT

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Re: Headlights dim and pulse - 68
« Reply #3 on: November 23, 2024, 07:17:00 PM »
Thanks for the replies! Maybe In should try a relay in my lighting circuit. I installed a new headlight switch, probably back in 1990, when I got the car on the road following restoration. Any suggestions for a headlight relay brand? Silly question, where/how do you wire it in?

How about my blower motor speeding up and slowing down a bit? Possibly replacing the voltage regulator would cure that?

Thanks again!
VIN 7T01C246XXX
Actual build date 5-11-67

VIN 8F01J208XXX
Actual build date 6-27-68

Offline 68 GT

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Re: Headlights dim and pulse - 68
« Reply #4 on: November 23, 2024, 07:18:10 PM »
Oh, pretty sure my headlights are halogens, forgot to state that in my last reply.🙃
VIN 7T01C246XXX
Actual build date 5-11-67

VIN 8F01J208XXX
Actual build date 6-27-68

Offline midlife

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Re: Headlights dim and pulse - 68
« Reply #5 on: November 23, 2024, 09:10:13 PM »
Halogen lights will definitely trip the internal circuit breaker in the headlight switch.  A relay is your best bet (but of course, it isn't concours correct).  Rocketman Classic Cougar Innovations makes relays and has a great reputation.
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