harryfrank

Good day, i have a w211 2006 e350 and the highbeam is stuck on. I've had the car for a while now, and I always kept the rotary in the AUTO position. the green light would turn on when needed once it got dark. if i needed the high beam, i would pull or push the lever on the side of the steering wheel accordingly. Starting a few weeks back, the lights go to high beam (blue icon) automatically, and the lever does not respond.

The last thing i noticed before all this, and not sure if it is related, is that I had a bad light beam and the lights would automatically switch to high beam. however, when this happened, i would a message that the low beam bulb was bad. I am not getting any messages now.

It has nothing to do with the constant option on the cluster, because i have it off.

Weird thing, is that one time i turned the switch all the way to the right, pulled it to turn the fog lights on, moved the lever and the lights blink twice!. it seemed to do the trick, but it started with the same issue next morning.

Any ideas? Have a long trip ahead of me, and i would hate to be puledl over because I am driving on the highway like this.

Thanks!

CaliBenzDriver

I don't have a silver bullet to tell which of the few suspects is messing up you high beams. First of all you should test the low beam reported bad....

At the end of the day HL power switching is done by F-SAM based on all the inputs (Lt sensor, steering stalk, rotary sel).

A poor GND or soaked HL connector can mess up this party too.

Use an OBD scanner to troubleshoot this function with faults and live data.

harryfrank

Yeah, it definitely needs more troubleshooting that I can probably give it now, given the trip circumstances. I am going to have to drive with the switch in that position for now. Thanks for the input.

harryfrank

Good day! I was able to do accomplish my 2200 mile trip by unplugging the high beam and driving during the day. I have now taken the headlamp assembly apart and found all wiring lost it’s insulated material and therefore probably was touching . All these on the low beam side though. I had to replace all the wiring, or better said insulated all with thermal shrinking tube. Because these wires run inside the head assembly, it seems like the heat was the cause of the fast degradation. The typical kind that we see in some older Mercedes (like a c230 back in the 90’s). The high beam side however, is a couple of direct plugs that seemed pretty decent, no cracked cables.

After all these the issue went from flashing high beam to a constant high beam. 😢.

so I went and replaced the front SAM unit for a used one. The problem seems to go back to original with the flashing lights, so I am going to put the old SAM back.

i am attaching a video where you can see the flashing lights with no one in the car.

if anybody know all or other reasons what could trigger the high beam, please let me know. Mar car is a 2006, so it does not have the adaptive option. And I have the running lights off for now, btw, they respond well to the cluster programming.

thanks

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