Headlight Bulbs Constantly Shorting
12-17-2015, 11:57 PM
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2002 C230
Headlight Bulbs Constantly Shorting
My '02 C230k goes through headlight bulbs like crazy. I'm having to replace both left and right (though never at the same time) at least once every 2 months. These are standard filament and not HID. Has anyone else had a similar problem? Here are some observations of the issue I've made over months of just replacing the bulbs not wanting to think too much of it:
-Only low beam has this issue. Park, side marker, tail, and fog lamps are fine.
-When inspecting the bulb's filament, it is always obviously melted and separated, as opposed to burned, exploded, or unchanged.
-New bulbs work 100% of the time, never flicker or delay illumination until they eventually never light again.
-Starting the car does not cause their failure, I've had at least 2 situations where they die while driving.
-Have never had a fuse blow in the headlamp circuit or anywhere else
**Although possibly unrelated but notable, I cannot turn off the headlights 3 minutes after starting the car. Before exactly 3 min if I select the 0 position on the control module, the lights will remain off. After 3 min, regardless of the selection on the module, the headlights will remain on until the engine is switched off. This is true for day and night.
I should also mention, the first time this happened I dropped $50 on Sylvania Ultra bright bulbs - which I am assuming have a higher wattage tolerance. All bulbs bought prior are bargain brand whatever-autozone-has-in-stock bulbs which comparatively, most likely do not have as high of a wattage tolerance; although their life span is not noticeably different from their expensive competitors'.
My thoughts range from: I should be buying bulbs from Mercedes, there is a wiring issue inside the headlight or harness leading to it, or there is a fault in the front SAM N10/1 logic. Any insight would be of great help!
-Only low beam has this issue. Park, side marker, tail, and fog lamps are fine.
-When inspecting the bulb's filament, it is always obviously melted and separated, as opposed to burned, exploded, or unchanged.
-New bulbs work 100% of the time, never flicker or delay illumination until they eventually never light again.
-Starting the car does not cause their failure, I've had at least 2 situations where they die while driving.
-Have never had a fuse blow in the headlamp circuit or anywhere else
**Although possibly unrelated but notable, I cannot turn off the headlights 3 minutes after starting the car. Before exactly 3 min if I select the 0 position on the control module, the lights will remain off. After 3 min, regardless of the selection on the module, the headlights will remain on until the engine is switched off. This is true for day and night.
I should also mention, the first time this happened I dropped $50 on Sylvania Ultra bright bulbs - which I am assuming have a higher wattage tolerance. All bulbs bought prior are bargain brand whatever-autozone-has-in-stock bulbs which comparatively, most likely do not have as high of a wattage tolerance; although their life span is not noticeably different from their expensive competitors'.
My thoughts range from: I should be buying bulbs from Mercedes, there is a wiring issue inside the headlight or harness leading to it, or there is a fault in the front SAM N10/1 logic. Any insight would be of great help!
12-18-2015, 01:33 AM
#2
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Those "ultra bright" bulbs and friends 'overdrive' the filament in a sense, and have shorter life than "standard" ones. But not in months!
Try maybe the osram rallye 65w bulbs. They are higher wattage bulbs in an h7 housing.
No idea about electrical issues potentially causing the burn-out, but as you noted it is unlikely since the other bulbs are okay.
Presume you are handling them with care/not touching the glass with bare hands etc.
Try maybe the osram rallye 65w bulbs. They are higher wattage bulbs in an h7 housing.
No idea about electrical issues potentially causing the burn-out, but as you noted it is unlikely since the other bulbs are okay.
Presume you are handling them with care/not touching the glass with bare hands etc.
12-18-2015, 05:49 AM
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2003 C230K Coupe Orion Blue
Not sure if it's related, but I remember reading something about a recall with bulb connectors corroding or otherwise going bad for 2002. Wondering if it's creating some short that's causing too much juice to go through your bulbs.
