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Headlight bulb failure / Ballast Failure

Discuss problems you have had or are having with your Z4
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FAARN
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Re: Headlight bulb failure / Ballast Failure

Post by FAARN » Mon Mar 18, 2013 7:21 pm

I think the same has happened to me although looking for clarification. My Xenon light failed today but I don't think it is the bulb or power unit that attaches to it as I have tried another of each and it still doesn't work. Only one side so not fuse (which i have checked). That would leave a faulty ballast; correct?

There is condensation in the headlight unit and it appears the seal isn't working too well. But presumably the ballast going has nothing to do with the back seal?

Unfortunately I need the car tomorrow so will have to drive with bulb out, I then have to leave it in the elements for 3 days (not happy but short notice trip with work). I don't have time to take the ballast off and dry out etc.... do you think the 3 days would damage it beyond repair?

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Re: Headlight bulb failure / Ballast Failure

Post by spearman » Tue Mar 19, 2013 8:47 am

More than likely ballast. There's only three potential point if failure in my opinion - bulb, ignition & ballast. If you've changed the bulb and ignition it'll be the ballast. They're about £120 new from eBay iirc.

Doesn't take long to get the bumper off then its a 10min job.

When mind sent I had a bit of condensation. Get a new backing plate cover - think part numbers are listed in previous posts (approx £10). You'll need to dry out the inside to.

Good luck!


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markeg
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Re: Headlight bulb failure / Ballast Failure

Post by markeg » Tue Mar 19, 2013 8:53 pm

+1 on ballast and replace the back covers & seals. I bought one for £90 on eBay, second hand with a years guarantee. New ones were £120 with a years guarantee also....


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FAARN
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Re: Headlight bulb failure / Ballast Failure

Post by FAARN » Sat Apr 13, 2013 6:15 pm

Well took bumper off again (getting good at this now) and took light off. Poured an eggcup of water out and dried with hairdryer. Turned the seal around and put everything back together. Took off the ballast, opened up to find more "stalagmites" than than a damp seaside cave in there! Luckily I had a spare.

The first time I put the back on I caught an electrical wire in the seal. I only noticed as I did a thorough look after fitting back cover (easy when headlight not fitted to car). I would not have noticed if I was putting the backplate back on in situ so worth making sure all wires are tucked well inside. This may be why so much water got in in the first place.

Unfortunately i also noticed a small crack underneath the ballast. Covered with tape now but not sure if it will leak. Have driven it in the rain and only the smallest amount of condensation in the light now (could be legacy, fingers crossed).

Anyway thanks for all the advice. I really was sold a lemon with the light but it was basically free with the other one.

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Headlight bulb failure / Ballast Failure

Post by Fermat » Sat Jan 05, 2019 9:31 pm

Thought is best to resurrect this thread, as it is the most appropriate I could find, and it never seems sensible to open a new thread just for the sake of it.

I have a Z4 Coupe (57 plate) which has been developing a headlight issue for a little while.

Initially the dipped headlight would not light up sometimes, and gave a bulb out warning on the dash. This only happened rarely, and turning the light off and back on again seemed to solve the issue. Recently, the same headlamp has started flickering every time it turns on and then it turns off with the same bulb out warning on the dash, so something is now properly dead.

As far as I am aware the headlamp is factory and has not been opened or touched. There are no obvious signs of condensation or water in the headlamp.

I was just wondering whether anyone has a view as to whether that is likely to be the bulb, or more likely to be the ballast?

I did briefly look at some of the part referred to in this thread, like the Hella ballast, but that is not longer available. Would I be best just to do this with OEM parts, as I am not really doing an upgrade on the headlamps at all?

Thanks

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