Like many of you, I have the dreaded "melting insulation" and "melting socket" on the lowbeam bulbs and it's caused the passenger light to flicker on and off for a couple of months. I could usually "Fonzy" it with a light tap to bring it back, much to the wife's amusement, but that couldn't go on forever.


(Just moving the socket made 90% of the insulation disintegrate)

The first time I looked in there I was worried that the wires would short and cause a fire or blow fuses, so when I saw how bad it was getting I re-insulated the positive wire with a short length of silicone vacuum hose, slit lengthwise and zip tied around the wire.





So I went online and bought a replacement ceramic socket for H7 bulb with welded connections and much heavier duty stranded wire. It cost less than $5 delivered slow boat from China. ( $5 on Amazon Prime now) (What Mercedes should have used...). I cut and wired it in, then moved my piece of silicone tube over to the highbeam wire, as the insulation was falling off of it too.



You can't really see it, but on the red + wire, I also added a length of shrink tube all the way back to the power input. It will probably melt off if it gets hot again, but at least that covered up the cracked and disintegrating insulation. Each joint is insulated with two shrink tubes, one short small one and one long large one.

Tucked it all back in:



Then, to keep it from getting so hot again (I live in Florida...) I drilled some ventilation holes in the light cover. I put small holes up under the top lip and angled them up as much as possible to keep water out.



Plus 4 holes straight up from the bottom to let cooler air in.



Hopefully that will keep the rest of it from melting. I have another ceramic socket for the drivers side, but with the ABS unit right there, it's kind of tight. I'll wait for it to get dicey first. I ventilated that side like the passenger side, so hopefully that won't happen.

 

I had this exact same problem...I replaced the entire headlight assembly, and still have this problem, the low beam doesnt want to work?

 

Ive tried 3 different bulbs. The light actually works when I shut off the car , turn off the lights and lock the door, the 10 second safety lighting works.