Headlamps, fiber optics brighten and dim alternately

My wife’s '05 Magnum SXT headlamps and toys lit up w/fiber optics alternately go bright then go dim but not at idle. I replaced headlight switch for heck of it and just made a deposit at Bank of Chrysler. Sounds like a ground? How best to find it - duh!

I would have the charging system checked. Many auto part stores will do this for free.

Checking grounds is also a very good idea, as well as both ends of all battery cables, but this are not free unless you are doing them yourself.

Thanks for the advice, Joseph. Will give it a shot. You wouldn’t have any suggestions on how to cure my wife’s “original curb impact designs” on the chromed American Racing TorqThrusts I put on her Magnum?? (Just kidding on seeking the advice - not kidding about the curb impacts - plural.)

Thanks again.

I agree with Joseph. This sounds like an alternator or regulator problem.

And thank you, too, the same mountainbike… For what it’s worth, this car’s cool-looking but the German influence in the electrics suck. Look at the speed control setup… The electrics have been nothing but trouble. The horn ring went out, the dash cluster had to be replaced, and now this…