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Xenon HID - One headlight yellowing - is it the bulb or transformer?

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Old 09-10-2007, 12:48 PM
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Default Xenon HID - One headlight yellowing - is it the bulb or transformer?

One of my xenons is noticeably yellow (as yellow as a crappy halogen) while the other one is a nice white color. Reading some old posts I found that sometimes the transformer can go bad; how can I tell whether it's the bulb or the transformer (or something else) that has gone bad?
Old 09-10-2007, 12:57 PM
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Probably ballast or the housing melting...
Old 09-10-2007, 12:59 PM
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Default switch them and see...

i'm guessing it's the bulb.
Old 09-10-2007, 01:04 PM
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Default Re: switch them and see...

I gather from reading some old posts that it's easier to remove the headlight assembly in order to get the bulb out... any write-ups on how to do that?
Old 09-10-2007, 01:38 PM
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See tech section. There are a few...The whole thing takes about 20 mins, if you don't drop any bolts
Old 09-10-2007, 02:02 PM
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2nd. HID bulbs get darker(loose luminescence) over time, and usually a more blueish hue.
Old 09-10-2007, 02:07 PM
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Default Color shift is normal as a HID lamp ages. If it were the ballast the lamp would cycle...

on and off or not ignite at all.
Old 09-10-2007, 02:12 PM
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Default Re: Color shift is normal as a HID lamp ages. If it were the ballast the lamp would cycle...

I wouldn't mind too much if they were both changing similarly but one is so much yellower than the other that I can tell from the illumination the headlights cast on a garage door for example.
Old 09-10-2007, 02:17 PM
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Default You can try swapping bulbs L to R Don't touch the glass, the color should follow the bulb..

Keep in mind even if you replace one bulb the color, and lumens will not match the other.
Old 09-10-2007, 02:23 PM
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Default A link to a little HID info for you. Not the best I've seen...

Just ca find the other site.<ul><li><a href="http://faqlight.carpassion.info/hl-hid-bulbs.htm">Linky</a></li></ul>


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