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Dim Xenon headlights

The Xenon headlights on my 2002 Mercedes ML320 are so dim I could light a match and see better. Is it the bulbs, the ballast, or the maybe the self leveling is out of whack somehow, Any suggestions???

How about your headlight covers? Are they yellowed? This will cause the headlights to appear dim.

Are the bulbs themselves dim or is this a matter of bright bulbs but not much light output?

Dim bulbs could point to a ballast problem, etc. and the latter could point to a dulled and/or burnt reflective surface in the headlamp housings along with dulled clear lenses.

The headlight covers have a slight haze due to road grime, but not significant. Mercedes dealer states the lights are fine but if I turn the headlights off and activate the flash to pass Halogen lamps, there is an obvious difference.

If you can, ask the mechanic/service rep to ride along with you at night time. If they have a used 2002 on their lot with similar equipment, ask to have it brought into the shop, alongside yours. Then ask them to turn the lights of the shop off, and the headlights on on both vehicles. If there is ANY difference in light output between the two, look at them and tell them to fix it right.

if I turn the headlights off and activate the flash to pass Halogen lamps, there is an obvious difference.

There should be a big difference. That’s the way they work.

Frankly I believe those fancy lights are all about hype and not about useful light. They sell because people don’t want to be the only ones with last year’s technology, even if it is no better. The manufacturers love it because they are profit makers.

The old sealed beam lamps (ideally E-codes) light very well, are cheap to replace, don’t have problems with weather and age damaged covers or motors etc. We won’t see them back any time soon because the fancy boys in the design departments love the style of the new lights and could care less about lighting the road.

“The Xenon headlights on my 2002 Mercedes ML320 are so dim I could light a match and see better. Is it the bulbs, the ballast, or the maybe the self leveling is out of whack somehow, Any suggestions???”

Benz over…

Nobody at the dealership is going to have either the skills or tools to diagnose the problem. Their only option is to swap parts until they fix it.

I would ask how many hours are on the lamps? They degrade over use just like any lamp. Just because they strike an arc doesn’t mean the ballasts cannot be at fault but the most likely suspect is the lamps, especially if they are on all the time (DRL).

Those sealed beams on the Chevelle I had didn’t project far enough out down the road unless I had on the high beams(all 4 lights at the same time). Compared to my Civic, it was crap.