I keep reading differing opinions on the lifespan of xenon bulbs. Some sources say that xenon lights last the life of the car, now I've just read on Powerbulbs that the D2S (as used on my car) last about 5 years?

:wonder:

Also, what's the process for changing them? I've done a search and there's mention of disconnecting the ballast.... but - disconnect the bulb from the ballast or the ballast from something else? And which bit is the ballast? Anyone got any pictures?

Mine lasted over 140,000 miles on my Octavia. I changed them as a matter of course as I suspect they were probably dimmer than when they were new.

The ballast will look like a metallic block near or behind the light fitting that boosts and regulates the power supply to the xenon burner.

The striking voltage can be over 20,000 volts so caution is advised.

The lamp change took me about an hour for both fittings, the lamps are held in with 2 small torx screws, the ignitor is built into the base of the lamp and connects to the ballast via a steel braided cable. This refers to the Octavia 2 and I am not familiar with the Octavia 1's xenon configuration.

On the Polo, it's a bayonet (I think), so like a household light connector from the ballast, to the burner. In essence, it's pretty much the same as a normal car light setup, only rather than clipping on, it screws on from the ballast, instead of the loom. Once that's off, I'd guess something like above, but never seen an Octavias setup either.

The xenons on my '02 plate were getting a bit tired (bluey and dim) so I changed them last year. The new ones (Philips OEM) are so white white that they actually barely look any different from halogen projector lights, BUT there is a good improvement in brightness.

Ok, so they do need replacement eventually then, even if they haven't actually failed. That's good. Thought I was going mad!

(I first wrote this elsewhere)

If it helps, when our car was a little over 6 years old we replaced the oem hid bulbs. We'd had problems approaching nearside hazards too quickly, in that sometimes hazards suddenly came into view closer to the car than you'd like. The garage checked and said the lights were correctly adjusted. After thinking about it for a while I ordered some new bulbs and asked the garage to fit them. Afterwards the problem hasn't recurred and we have more confidence in the lights.

I found that hid bulbs get dimmer as they age, (see manufacturers' data, or a datasheet), and that turning them on and off too frequently isn't good for them either - I think they need to cool down significantly before being switched on again. It's not something that's widely discussed, and it's hard to find concrete information. As a consequence I try not to switch on the dipped beam unless I'm convinced I'll not be needing to switch them off for a while, and I try to avoid switching them on too soon after switching them off, (although I don't know what too soon is).

Regarding our particular problem, I suspect it may have had something to do with the different beam pattern for (legal) hid bulbs, in that they don't have the 15 degree wedge of light to the nearside that normal headlights have, (they have a step up to the nearside instead), so they don't cast the main pool of light so far forward at the extreme nearside. This in turn means a driver relies more for forward vision on the small amount of light that is emitted above the main pool of light. All supposition on my part, but we're convinced the replacement bulbs give a better light.

Cinema projector Arc lamps have the same lifetime decay, which is why they need replacing after a similar time scale.

A search online should reveal that sort of data by searching based on arc rather than HID

I have always wondered that if you travel to Europe, do you need to buy a spare Xenon bulb, because a bulb kit is a requirement?

I have always wondered that if you travel to Europe, do you need to buy a spare Xenon bulb, because a bulb kit is a requirement?

That has been raised in the past.

When I enquired with one motoring organisation I was told no, as a HID unit is not technically a bulb. However I'm not sure how you would argue that with a stroppy Gendarme! Personally I think I would keep a kit with a H4 bulb in it and hope for the best.

Whilst we're on xenons, where do people get their replacements from? I seem to only be able to find xenon effect, not actual xenons.

Powerbulbs do a D2S replacement for £45 each side. And you get 15% discount for being Green!

http://www.hids4u.co.uk/osram-d2s-xenon-hid-headlight-bulb.html

£69.99 for a pair.

Edited 27 February, 201115 yr by kenny rsell

http://www.hids4u.co...light-bulb.html

£69.99 for a pair.

Thanks, that looks good!

Just bought 2 Phillips replacements for £45 from hids4u using discount code STRATHY.

I found that hid bulbs get dimmer as they age, (see manufacturers' data, or a datasheet), and that turning them on and off too frequently isn't good for them either - I think they need to cool down significantly before being switched on again. It's not something that's widely discussed, and it's hard to find concrete information. As a consequence I try not to switch on the dipped beam unless I'm convinced I'll not be needing to switch them off for a while, and I try to avoid switching them on too soon after switching them off, (although I don't know what too soon is).

This is the main reason why I had my coming home/leaving home lights altered via VCDS so they now use the fog lamps and don't fire up the expensive Xenons every time I approach or leave my Yeti. For their purpose (to show you were you are walking) the fogs give ample light and you really don't need Xenons for that! :no: As a bonus they now also fade in and out slowly instead of the BANG! and they're on Xenons. (The Xenons don't do their setting up dance when used as coming home/leaving home lights).

Fitted my new lamps yesterday, went out last night,can only say if your car is more than 5 years old it is worth £45 to change the lamps.the lamps must dim gradually over time that you do not notice, put new lamps in and what a difference,as said above much whiter and less blue. Wish I had done it before the start of the dark winter nights.

Fitted my new lamps yesterday, went out last night,can only say if your car is more than 5 years old it is worth £45 to change the lamps.the lamps must dim gradually over time that you do not notice, put new lamps in and what a difference,as said above much whiter and less blue. Wish I had done it before the start of the dark winter nights.

I don't know if the ballasts age too, though. The xenons in my mk1 Octy are vastly inferior to the ones I had on my mk2 Octy, but then again, that might be down to a better headlight design in the newer model.

Hmm my car's nearly seven years old. Only done 102,000km so far though and mostly in daylight I think.

They don't seem to be any dimmer yet.

Hmm my car's nearly seven years old. Only done 102,000km so far though and mostly in daylight I think.

They don't seem to be any dimmer yet.

After a few thousand hours of ontime there will be metalic vapour, that has deposited on the upper layer of glass, so you'll get at least some diming effect.

It's one of those things that is so gradual it would be hard to notice.

FWIW, if you take one of the bulbs out, you can easily check if there is this deposit on the top inner face of the glass.

If your bulb design allows it, turn the bulb so that this is now at the bottom and you'll get improved output, but eventually they will need doing.

Never noticed that when I took the lamps out,but yes there is a deposit on the inside of the glass.Can't see it so well in the photo though.