E46 M3 Xenon Headlight Failure

[mat205125]

Whats the sequence of checks and tests that I should perform to identify which parts I need to replace to fix a failed Xenon headlight? I've no experience of Xenon technology at all to fall back on.

[ghibbett]

First thing is to swap xenon bulbs to see if you move the fault.

If not, then remove both headlamps and swap the ballast packs. 99% chance it'll be either of these two.

I have a great step-by-step guide somewhere. Will fish it out and post back.

HTH

[ghibbett]

Oh here it is:

Changing Xenon bulbs: http://forum.e46fanatics.com/showthread.php?p=8554...

Removing headlamps to change the ballast and ignitor: http://www.bigpatsfans.com/hl/headlight.htm

Taking your complete headlamp apart: http://forum.e46fanatics.com/showthread.php?t=6095...

Thank god for bookmarks

[MattOz]

Nice links Grant. Will probably come in handy at some point.

[ghibbett]

No worries mate. They're the links you don't want to have to click tho. Xenon bits aren't exactly cheap.

[Ruskie]

Don't rush in is my advice!

My xenon (E46 330) failed, swapped bulbs and was not that. Booked it in to have unit replaced (Can't remember which bit) However it came back on and stayed on for 6 months, went off again for 2 days then came back on, that was another 6 months ago! Very strange but it is still going strong 12 months after the initial problem.

[mat205125]

Thanks for all of the information so far. Very interesting to hear peoples experiences.

I'll try and find some daylight time over the weekend to swap the bulbs to see if that looks like the problem.

[Crusoe]

Need a lot of charge to switch on, one of mine didn't light first time when I came back from holiday, took the car for a good run to top up the battery and they both came on fine after that. Might be worth checking by trying them on after you have had the car going for a while not as soon as you get in the car.

[mat205125]

Crusoe said:

Need a lot of charge to switch on, one of mine didn't light first time when I came back from holiday, took the car for a good run to top up the battery and they both came on fine after that. Might be worth checking by trying them on after you have had the car going for a while not as soon as you get in the car.

The "failed" bulb does flicker as if its trying to come on, kinda like a Motel neon sign from a bad horror movie.

I'm not sure what other people do, but I've always got my light switch in the auto position, so they try to turn themselves on before the engine starts.

I'm reasonably confident that it must be the bulb that has died, as for the week leading up to the failure it progressively changed colour from a pink (which the GF liked!) to an orangy red, then nothing at all ... I'd put money on it being burnt out.

[ghibbett]

When mine went it was flickering, although the progression from flickering to being totally out was only a minute or so. In my case it was the ballast unit. Easy to replace but they cost ~£300 from a BMW dealer.

[Ruskie]

Make sure your sitting down when you see how much the parts are!