Montreal300

The car is a 2014 SL550 with Zenon beams.
The problem is that when the car is started in the garage the headlights (low beam) come on, like they are supposed to, but after 15-20 seconds the drivers side shuts down. The cornering lights on the drivers side are also off but turn and parking lights still work.
If I flick the high beam on, the drivers side high beam comes on for a second and then goes back off. The passenger side stays on high beam. I can do this multiple times.
Has this happened to anyone else?
I'm looking for a simple answer before I have to open everything up to get at the headlight and modules.

Thanks in advance.

Jimbo2518

My SL550 is a 2018. I have had a recurring issue with the headlights which are a known problem. The entire headlight assemblies are not sealed (engineering failure). On my car moisture builds up inside the headlights and and eventually finds its way to the electrical connection. When this happens all kinds of random electrical faults occur (such as yours). In my case, I have had every major system stop functioning while I was driving (no power steering, no power brakes, nothing registers on any gauge on entire console, etc.) Fortunately for me, I purchased the extended warranty and all the repairs, which are extensive, have been paid for by MB. After the first complete failure MB (via the dealership) did their standard Mickey Mouse fix which involves drilling holes in the headlight assembly and adding silica crystals to absorb moisture. (So much for MB engineering excellence). With the second failure I explained given the service record with the vehicle the liability exposure for the dealership and MB was well into the many millions of dollars if another failure occurred and I, my family, or someone else was injured as a result of their sweeping this known fault under the rug.

I tell you all of the above is I suspect you likely have some water in the headlight that needs to be addressed before the repairs become more extensive. Best of luck.

Wolfman

Jimbo2518, sorry to hear about the moisture issue. Definitely something I have seen in different models (W222 S-Class) but personally never experienced any extended moisture.
It would be great to see geographically where these issues occur most. High humidity like Fl or?
Make sure to get a new headlight assembly on any re-occurrence. The dealer can easily push that to MB to authorize.

ThatsMyDawg

And their response to this statement was?

Jimbo2518

Wolfman, I have owned the vehicle for 2.5 years and it is a magnificent car that is kept in pristine condition. I live in Metro Atlanta and humidity may play a role but I believe the problem extends beyond ambient temperature and humidity changes. To my knowledge the vehicle has never been in an accident, especially to the front end. The car has been back to the dealership no less than 5 times for service regarding varying degrees of moisture in the headlights. Initially, the problem looked liked raindrops sliding down the inside of the headlight lens cover. Next it progressed to complete fogging of the lens. The dealership replaced the driver side unit (which was in the worst condition). That helped for a few months but the problem returned. That is when the first complete system shutdown occurred.

After another visit the dealership "resealed" the unit, drilled holes in the rear of the unit, and put in silica crystals. Again, things were better for a few months but the problem showed up again. Recently, I experienced the second complete system shutdown. This time they removed the front bumper, replaced both complete headlight assemblies, all connectors, etc. According to the Service Advisor, when they removed the driver side headlight assembly "water poured out". I have only had the car back in my possession for two weeks and so far all is good but time will tell if the issue has been resolved.

The dealership, and to my knowledge MB, has been alerted to the major liability posed by this issue. The history of my ownership of the vehicle and its service record are preserved in the dealership records. It the issue never returns all is well. If it returns I will have my attorney draft letters to the dealership, MB, and my insurance company stating we are holding them responsible for all liability and will seek damages if any or anything is harmed.

The truly sad part of all this is I believe MB has been aware of this problem in many SL's but has chosen to basically ignore it in hopes the models will just fade away along with the problems. The idea that drilling holes in the rear of the unit and adding silica crystals to absorb water does not appear to be sound engineering in my judgement. I have seen this problem discussed on this forum and other MB related forums.