Ugh, is this a bad voltage regulator?

[Jessie James]

I started up the truck and turned on the headlights and they go dim for a few seconds (just a bit) then brighter for a few seconds ... repeat endlessly.

Voltage regulator? Right? I really don't want to have to pull the alternator as it's 20 degrees out ... probably going to be less for the whole week.

 

[Blue85]

Is the engine speed consistent or is it dipping down? Is there anything on the vehicle that could be drawing an intermittent load like that? If not - a new alt is in order. It might be a little more comfortable doing the swap when the engine is sort of warmed up. Or call a buddy with a garage...?

 

[str8axle55]

I was out working on mine when it was 22 out the other day. Warm it up for a little bit and pull the alt off, shouldn`t take that long. You should be able to have it tested at on of the big parts store chains.

 

[Jessie James]

Is the engine speed consistent or is it dipping down? Is there anything on the vehicle that could be drawing an intermittent load like that? If not - a new alt is in order. It might be a little more comfortable doing the swap when the engine is sort of warmed up. Or call a buddy with a garage...?

Yes, engine speed is consistent, and there isn't anything that should be drawing a load, it's been fine for the past 2 months (since I bought it).

I guess I'll have to pull it and test it. Yay.

Thanks for the tips, guys, I appreciate it!