All lights pulsating

[Devin]

I decided to start a new thread because the old one was getting cluttered.

So to make a long story short, got my car re-licensed, and that day I got a flickering battery light. Measured the voltage and it never got higher than 13.8. Took the alt in to a rebuilder and they said that the alternator worked fine.

Three weeks later, the car has a flickering light AND all of the lights in the car pulsate with the RPMs. Higher RPM, faster pulsating. Over head lamps, head lamps, brake lamps, cluster, everything. It's like a soothing light show at low RPMs.

So I hook up my multimeter to it. Here's what I get:



Could this be anything BUT the alternator? Should I get the battery load tested? This is way above my head now, guys.

 

[yamahaSHO]

I'm going with the voltage regulator housed in the alternator.

 

[hawkeye18]

Yeah, your voltage regulator took a massive dump. If the battery were putting out 18.8 volts, it would have exploded, or created a subspace rift.

 

[Devin]

That's pretty cool: I got to see it die. When I started up the car yesterday it was putting out 16VDC to the battery. I reved it a couple times and it was still around 16-16.5VDC. Not 2 minutes later it started putting out 17VDC then 18VDC...

After I turned the car off, the battery was reporting between 16.5VDC and 17.0VDC.

I'm going to have the battery tested anyways to see if it is healthy or to see if it killed off the alternator. I want to test the alternator again anyway to see if it is reproduceable.

 

[hawkeye18]

An alternator putting out 18v would have killed your battery in short order; 18v will sulfate the plates nearly instantly.

 

[yamahaSHO]

I'd stop running the car with that voltage. The battery isn't giving you the high voltage, it is the alternator.

 

[Devin]

So I ended up getting a replacement, and all appears to be well so far. The battery light is off and all the lights are back to normal.

I went to Sears to have them check the battery and he said it still held a full charge. I'm going to start driving it to work next week.


And I got a membership to AAA...

 

[sperold]

I would stay away from the alternator re-builder that gave your alternator a clean bill of health.

 

[trevhelton]

When I got a new alternator I had one that passed the test according the the little spinner thing in the stores. But it was bad had to drive and stall more than once then took it back when it was not working for sure and got it replaced. Stupid remans are a joke would rather have a brand spankin new one so I wouldnt have to do the work 4 times