Go back to that voltmeter across the battery, and you will notice that with the headlights on and engine from idle to reved slightly, the voltage will vary from 12.5 to 14.5 volts. That is not much, but enough to cause a noticeable flicker if anyone is paying attention. Most people do not notice.
But that is a good thing.
It shows the alternator is putting out more than the battery alone has.
It is when that flicker goes away, that you know there is something wrong with the alternator.
Put the voltmeter to AC and see if there might be some AC content in the cars DC voltage. While it is running. If not check grounds. What that means is look at a schematic that shows where the grounds are and see if they are clean and not rusty.
Read this article on GM headlight problems
http://ricksfreeautorepairadvice.com/hea...
Sounds like it needs more ground or the ground is a bit loose. Double check it.
Bad ground.
Simple short fuse probably . Cost $5 bucks
I have a 1999 Cadillac Deville. My interior and headlights flicker. Its not a bad flicker but its annoying. My first thought was alternator. Got my volt meter and the alternator was charging correctly. The battery is new, all cables are secure and corrosion free. What could be my problem?
