Low beam light failure?

2007 MERCEDES BENZ ML350
140,000 MILES • 3.5L • 6 CYL • 4WD • AUTOMATIC
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WILYUM
Low beam lights when driving are not bright enough to safely drive at night
Apr 23, 2026 at 9:27 PM
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STRAILER
  • ✓ASE Certified Mechanic
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  • ASE Certified Mechanic
So are the bulbs dim or are the lenses fogged over? If the bulbs are dim, also does this car have the Xenon lights? The bulbs are powered by the front SAM module which is under the passengers seat, I have seen this module get wet and corrode the electrical connections. I would disconnect the battery and remove the electrical connector from the SAM and check it. There is also a ground for the low beams at the right side headlight (brown wire). If this ground is lose the headlights will be dim, please go over this guide as well.

https://www.2carpros.com/articles/one-headlight-is-dim-or-dull

Please go over this guide and get back to us.


Apr 25, 2026 at 8:24 AM
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