Xenon headlight bulb replacement

[johnnydog]

The offside headlight bulb has failed on my 2015 RS4.
I understand the headlight unit has to come out to replace them which isn't a problem. However Audi want £253.32 EACH just to supply the bulb
Online for a recognised make, the prices vary from low £20's on Ebay (probably last a week ) to ECP and Halfords (Philips / Osram) round about £90 each. Halfords offer a 4 year warranty which seems a pretty good warranty. However, some units are rated at 4200k, 4300k, 4500k and 4600k. I appreciate it is good practice to replace in pairs, but what is the K output of the original units? It doesn't state on the old unit, and Audi Parts said their system doesn't say.
Anyone know the K figure of the original units? Or even the Audi part no?
TIA

[HPsauce]

If you get a pair it doesn't matter, but probably 4200K originally. A colour mismatch "can" be an MOT fail.
There are so many fakes out there (£20 eBay will definitely be) especially Philips, so Osram are more likely genuine.
£90-£100 each is the right price range.
First try swapping the bulbs, if you can, it could be the ballast that has failed.

[johnnydog]

Thanks HP.
Just checked the nearside as it is easy to access, and the originals are by Harison (made in Japan). A bit of Googling suggests that they are 4300K, so I'll go for that temperature figure. I don't normally use Halfords except if they have offers on, but with their Osram bulbs having a 4 year warranty at around £50, at least I should have some back up if they fail. They are listed as 4500K however. ECP only offer 1 year component warranty.
I'll try swapping them round initially just to confirm it's the bulb.
Thanks again.

[CusterDome]

Let us know how you get on Johnnydog, it would be a useful bit of knowledge to have with that kind of saving. £253 each!!!! Good Lord.

[johnnydog]

Just one more question if anyone knows the answer....does the RS4 have xenons or bi-xenons?
I think it's something to with xenons having two bulbs - one each for low and high beam; bi-xenons using just the one bulb with the movement of the reflector altering the angle of the beam. I'm thinking ours are bi-xenons, but of course most places don't stipulate which type their particular bulbs are...you wouldn't think a headlight bulb would be so 'technically complicated'.....

[HPsauce]

Bi-Xenons don't move the reflector. There's a tiny black shield, inside the bulb, that is moved electrically to change how much beam is available.
Turn your headlights on and look at them while getting someone to switch between dipped and full. With Bi-Xenons it's just one light each side which will change pattern slightly.
Hold a sheet of paper close in front to see this clearly.
Though some cars, and I don't know yours, can also have a pair of "full beam only" headlights.
The likes of Halfords should know exactly what you need.

And Harison are Toshiba.

[ant1]

Sure it’s not the ballast? 9/10 times it is.

[johnnydog]

I intend to swap the bulbs over first to rule out the ballast before I buy any replacements. That is if there's a fine spell over this weekend....

[RS144]

I run Osram Cool Blue Boost (CBB) on my RS4.
The bulbs are not road legal but I passed German TÜV without any issues twice already.
The beam pattern ist perfekt, the light color is pure white, the light output matches current LED Systems. Very happy.
There is a video on YT as to how to how to change the bulbs in an RS4, its an easy DIJ-job.

[johnnydog]

Swapped the bulbs over side to side this morning - the offside is still out, which suggests the o/s ballast is the fault.
Looks like I will now be best making use of my Audi Extended Warranty for the first time....
Good suggestion from ant1 and HP .

[Rusty Racer]

I had the same thing on mine, that was also the ballast. A cheap bulb can help with diagnostics.

[johnnydog]

Can you remember the cost of a replacement ballast? Or a part number? I can't see ballast alone being cheap from Audi if they are asking £253 for the bulb on its own. It's whether I can get a replacement ballast for less than the £250 XS that my extended warranty would cost me - they are simple enough to fit and just a 'plug and play', I understand.

[ant1]

Can you remember the cost of a replacement ballast? Or a part number? I can't see ballast alone being cheap from Audi if they are asking £253 for the bulb on its own. It's whether I can get a replacement ballast for less than the £250 XS that my extended warranty would cost me - they are simple enough to fit and just a 'plug and play', I understand.

I did quite a lot of research before ordering a ballast. Lots of people online use a cheaper ballast than the one in link below, i ordered from a trader that only sells this kind of item.

Identical to the original tbh. £39.99 delivered next day.

https://www.ebay.co.uk/itm/204210799165 ... media=COPY

[johnnydog]

Great! Thanks for that info!

[Rusty Racer]

Sorry bud, mine was done under the Audi warranty