I have had a loud high pitched noise coming from under the dashboard for a couple years that comes and goes and now my headlights have shorted out first the low beams now high beams
headlights shorting out and loud high pitched noise coming from dash on 1992 Lincoln Mark VII
I am concerned that you have an electrical concern that could progress and become an issue. I do not know what is causing the noise -- perhaps an auto lamp relay? Hard to say. Get it inspected locally, if you can, for a firtst hand oopinion.