Pulsing Lights Need Help.

Hi guys. Hope someone can help. I drive a 1995 Buick Riviera with the 3800 SC engine. The car has 194000 miles and i love it.
I have a nagging problem. I seem to have some kind of electrical issue. All the lights in my car constantly pulse up and down in brightness.
This includes headlights, dash lights, stereo lights, even interior lights. I checked the connections on the battery and every where i could see.
Did not find anything unusual. Engine rpm.s do not fluxuate so i was wondering if any of you had the same problem.
I look forward to any advise you can spare.
Thanks
Rick

Sounds like you could have a bad voltage regulator, but there are many other things to check out first.

Are the grounds clean? The batter under the back seat grounds to the body there. There is a major ground point on the body under the hood near the transmission lines/radiator.

What does a voltmeter tell you? If the car is idling and the lights are fluctuating do you have steady voltage or is it going up and down as well?

There are many other possible things to check/clean on the electrical system, but first we need to know if it's the entire system voltage that's fluctuating, just the lights, or if there are other conditions that need to happen for the pulsing to occur.

My $0.02: Voltage regulator is either loose or has corroded connections, or is internally failing. The regulator is in the alternator. You can take the alternator apart to fix, easier with an air impact wrench to get the pulley bolt off. Instructions are posted around the WWW and come with some replacement regulators (available at local full line parts stores and RockAuto.Com.

By the way, did you disassemble the electrical connections when you checked them? do tell...

Albertj

Thanks Guys. I will check these suggestions and get back to you. As far as checking connections i just looked for visable issues and tightness.

mulchman61 wrote:

Thanks Guys. I will check these suggestions and get back to you. As far as checking connections i just looked for visable issues and tightness.

Hate to break it to you, but you really have to disassemble the connections. over time corrosion will creep under and between the ring and blade terminals and their mating surfaces. The good news is once you open them, clean them right, put on a little dielectric grease (tune up grease, you can use syl-glyde for brakes, or tune up grease in teh little tube, or any similar dimethylpolysiloxane grease) or "NoAlOx" conductive grease that electricians use on aluminum. Done right once you might not have to mess with them ever again.

How to decide which grease - use dielectric (nonconductive) grease on the multi-terminal connectors so you don't accidentally bridge conducting paths between pins. Use Noalox on the big ring terminals like the big chassis ground on the frame rail near the starter.

I still think you're in to replace the voltage regulator (if you can disassemble the alternator) or replace the alternator as a unit (if you don't have an impact wrench to get the pulley off the alt).