Lights pulsing

[Bob S]

With known-to-be-good voltage regulator, my car at idle/low rpms provides constant voltage but at higher rpms when external voltage regulator "downshifts" ... the lights (all) will pulsate a bit. Is this a diode problem or something else in the (Bosch) alternator. THANKS ALL

 

[budgetzagato]

A possible solution

Often the headlight pulsing is caused by one of the brushes of the voltage regulator not seating properly in the wear groove. A pulsing like you describe can result.

I'd try removing and reinstalling the V.R. and see if it helps. Be sure to disconnect the battery ground first!

 

[Bob S]

To clarify

This is an external V.R. located in spare tire comp. Not mounted on alternator.

 

[Dayton Tom]

not sure on the issue, but...

I have one or two of the external volt regulators if you want them. I converted to a GM alternator a few years ago and haven't looked back. I bought the one new and only on the car for a couple of months. You can email me at TomMarcellino*hotmail.com with address if interested.

 

[budgetzagato]

I'd take it too an alternator shop for testing then.

It may be the same issue, or maybe something else. Either way it's beyond my set of skills and I let folks who know diagnose and fix.

I find that a starter/alternator rebuilder is the place to go, usually friendly and knowledgeable and willing to explain, and often cheaper and more reliable than a parts seller only. And often your core is better than their "rebuilt" one, but for the one thing wrong with it. Ask around the shops in your area and see what the most common answer is to the question "who do you send your alternators to?"