There are many many questions on this site about failed MF switches. Does anyone know why so many of them fail? Any service bulletins out there? I have had two failures on a 98 within a year.

 

Welcome to the forum

I've never seen a TSB on multifunction switches.
It's just one of those things that dies sometimes
It may depend on where you live too. Where I am we replace a few but not tons of them.

 

They have a corrosion problem. I just sprayed mine with WD-40 2 years ago and no problem since.

 

Besides corrosion, there is also a good amount of heat/amps running thru it. They have pretty small contacts so sometimes they just burn/melt. I would imagine those that pull back on it, to activate both low and high beams at the same time, have this happen more often.

Sometimes the plastic gears just wear out.

Pretty common for just about any brand though.