Faint flickering in all lights

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fmjcraig

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This slight flickering in all visible lights doesn’t affect charging, driving...noticeable in footwell lights when headlights are not on, alternator is fairly new, headlight switch is a new replacement, so I’m wondering if it could just be the voltage regulator needing to be replaced. Doesn’t appear to be speed or rpm related also...Ghost in the machine, would love to hear feedback suggestions and I bet it has occurred in others.
 

fmjcraig

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Yes, it is likely your regulator. They are electro-mechanical and some flickering is fairly common, as the contacts open and close. I would get an all electronic replacement.
Thanks...it currently has a voltage regulator that is painted (by the manufacturer) gray in color not the original light or dark blue (D2TF-10316-AA), and my car is factory equipped with a/c, so I will have to get the right one for a/c and electronic circuitry
 
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If you want an original looking one with the correct part number you can get the electronic voltage regulator from your local Ford dealer or parts store. I would try to get a Motorcraft one, do not get a Scott Drake regulator:

Then get the correct cover:
 

Hemikiller

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Before you throw parts at the problem, clean and re-seat the connections on your ground cable - battery lug, cable to apron tab, and block attachment. Clean the connections at the regulator, and make sure the regulator case itself is grounded well to the apron.
 

Bobby

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Before you throw parts at the problem, clean and re-seat the connections on your ground cable - battery lug, cable to apron tab, and block attachment. Clean the connections at the regulator, and make sure the regulator case itself is grounded well to the apron.
I agree. Flickering is most likely a loose or bad ground. All the related connections should be inspected, cleaned and tightened.
 

fmjcraig

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I agree. Flickering is most likely a loose or bad ground. All the related connections should be inspected, cleaned and tightened.
Thanks for the input from all...will update results later this spring
 

Ron Tanzi

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This slight flickering in all visible lights doesn’t affect charging, driving...noticeable in footwell lights when headlights are not on, alternator is fairly new, headlight switch is a new replacement, so I’m wondering if it could just be the voltage regulator needing to be replaced. Doesn’t appear to be speed or rpm related also...Ghost in the machine, would love to hear feedback suggestions and I bet it has occurred in others.
Ghost in the machine.jpg This ghost in the machine? LOL. It is your regulator. Mine did that with the original mechanical points type regulator. Make sure you get a good quality sold state version. There is a lot of junk out there.
Ron
 

fmjcraig

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View attachment 59306 This ghost in the machine? LOL. It is your regulator. Mine did that with the original mechanical points type regulator. Make sure you get a good quality sold state version. There is a lot of junk out there.
Ron
Thanks RON...can you suggest where to acquire the solid state version (I hear not Scott Drake)...my mustang does have functioning factory a/c so I believe I have to get a voltage regulator specific for that application. Thanks
 

fmjcraig

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Thanks RON...can you suggest where to acquire the solid state version (I hear not Scott Drake)...my mustang does have functioning factory a/c so I believe I have to get a voltage regulator specific for that application. Thanks
 
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The reason there was a different one for AC cars was a larger alternator and the electro-mechanical regulator. A modern Motorcraft electronic regulator will work fine. I posted a link to one on NPD on my first answer to this thread. You can also get one at a local Ford dealer or auto parts store. I have also had good luck with NAPA Echelon brand.
 

fmjcraig

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[url=https://ibb.co/cf86fv][img]https://preview.ibb.co/dT9ZYF/IMG_0225.png[/img][/url]
The reason there was a different one for AC cars was a larger alternator and the electro-mechanical regulator. A modern Motorcraft electronic regulator will work fine. I posted a link to one on NPD on my first answer to this thread. You can also get one at a local Ford dealer or auto parts store. I have also had good luck with NAPA Echelon brand.
Great and thanks! AMK D3TF...AA also looks correct for $42.
 

Ron Tanzi

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Thanks RON...can you suggest where to acquire the solid state version (I hear not Scott Drake)...my mustang does have functioning factory a/c so I believe I have to get a voltage regulator specific for that application. Thanks
I have never heard of a specific regulator for A/C equipped cars. It is really about the amp rating of the Alternator. Your car must have at least a 55 amp alternator. If anyone out there wants to correct me I believe all the regulators are the same for all applications. Last year in a pinch I installed an NOS Autolite mechanical regulator that was given to me 20 years ago by a friend when my solid state regulator (Standard) shit the bed and was overcharging @16 volts. Glad I caught that before the battery exploded. I would go with an Echlin form Napa. Especially if it is an older American made one. Most likely it will be.

Ron
 

Hemikiller

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Great and thanks! AMK D3TF...AA also looks correct for $42.

I've never heard a positive review on the AMK regulators. The Motorcraft GR540B or the Standard VR-166 (NOT the VR-166T) have the best reliability. I've also had great luck with scavenged OE Motorcraft electronic units from cars in junkyards.
 
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