Why are my headlights/interior lights flickering?

[Great68]

I've been having a strange problem with my car. (Most of the other ones have now been resolved )

Cruising along my headlights and instrument cluster will flicker, sort of like a rapid fade in/fade out.

It is more prominent while cruising at 2500-3000 rpm. At idle it doesn't do it as much. Could my voltage regulator be going bad?

My alternator is only a couple years old and barely has 5000 miles on it.

Appreciate the help.

 

[mfp4073]

First place to start would be the dimmer switch. Basically the part connect to the pull swtch to turn on the headlights. They are pretty cheap and easy to replace.

 

[Swede958]

My guess would be headlight switch, feel underneath the dash on the switch itself when it starts doing it and see if it gets hot. If it gets too hot, it will start to flicker the lights on and off. That's what mine did in my '70. I replaced the switch with a '67 cougar one (more amperage).

The Swede

 

[Great68]

Thanks guys, I will check that out tomorrow!

 

[WORTH]

Keep in mind your car wasn't designed to use halogen headlights, alot of guys have been wiring in a pair of relays to run the headlights to keep the headlight switch from overheating.

When Mine started doing that last year I just replaqced the headlight switch, and haven't had a problem yet, but if it does act up again I will go with the relays.

 

[GIDYUP]

I had a similar problem to this last year. It ended up being a case of a faulty dip switch (high beam) I replaced that and it went back to normal and havn't had a problem since.

 

[streetgrande69]

i personaly think its the voltage regulator. i'd prolly say you have a machanlcal and it a paulsating that is different speed with rpm. if you replace it get a ford replacement solid state(smaller box type)

 

[WORTH]

i personaly think its the voltage regulator. i'd prolly say you have a machanlcal and it a paulsating that is different speed with rpm. if you replace it get a ford replacement solid state(smaller box type)

If you use the solid state regulator and you want it to look stock, just drill out the 2 rivets and use your old cover with the original screws.

 

[my66coupe]

Im pretty sure you have a short somewhere in the system. My connection from the tail light harness where it joined to the underdash harness shorted, and yes there was a ton of heat. When I put my headlights on, they would be normal at idle, but after drving around for a bit they would flicker and dim. Go under the dash towards the fuse box and feel around for any hot wires, fix or replace them. But ya I would check if your taillights have been acting screwy too. Good luck

Mike

 

[SLEEPERstang21]

My dash lights don't even come on...everything else works. What can I check to see what the problem is???

 

[Clapper]

I went through everything and it turned out to be my positive battery cable.

 

[RaggedGT]

I went through everything and it turned out to be my positive battery cable.

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