Hi,

Yes, there is a beam "dipper" relay that changes the beams from high to low.
It is located on the left side fender or driver side.

It is an oblong sliver metallic box with plugs coming up to the bottom.
Lots of times the terminals get corroded due to their position.

The box can be opened for inspection, after you uncurl the tabs along its base.
You might want to do this to look for moisture infiltration.

You can hook up a battery to the coils terminals to observe the simple operation of the toggling arm that opens and closes the contacts to the beams. I have had one or two get sticky.
It's all mechanical and rarely fails but electricity gets "mad at resistances" and this causes heat.
Heat can build up until the circuit fails or its lights out in your case.

Again it's mostly the terminals.
It is why Art took you to the socket behind the vents. This is very common place on lots of cars.
I have not had that issue with any of my cars but I feel it depends a lot on humidity locations over the many years.
The use of anti corrosion sprays and paste being used during repairs in the area of all connections is worth the efforts!

IMHO

Phil.