Flickering auto lights

My son has a 2005 Subaru WRX. It has almost 60,000 miles on it. Recently he has noticed that the lights flicker. He says it is all the lights (dash lights, headlights, etc. He gets a low voltage warning on his radar detector when the lights flicker. We’ve had the car in to the Subaru dealer for this problem but they found nothing since this is an intermittent electrical problem. I suspect it must be something systemic like the voltage regulator on the alternator or some intermittent load on the electrical system. This is a new problem so it seems likely that something is wrong.

The problem might be with worn brushes in the alternator. If the brushes become completely worn out, it can expose the copper leads of the brushes where they come in contact with the slip rings in the alternator. And as the brushes wear, the brush springs provide less pressure to the brushes to keep them pressed against the slip rings. This then allows the brushes to bounce off and on the slips rings as they rotate. This then causes the lights to flicker.


Sounds plausible. We’ll look into that. I appreciate your speedy comment.

These Subarus, Is it not odd to have completely worn out alternator brushes at 60K? I am starting to believe these cars don’t fit the norm in regards to durability.

A factory alternator that can’t make 60K and Dealer Techs who can’t see this. Your luck is bound to change.

It does seem unlikely for alternator brushes to be shot after just 60K. In all the cars I’ve owned, this would be a first for alternator brushes. However, I had a Dodge Caravan that religiously ate transmissions every 70K. I dumped that jalopy after the second tranny. I hope you’re right about a change in luck! Thanks.