Intermittently working headlight, bulb dead or igniter?

evo · #1 3rd January 2014, 09:01 AM

So I've never had these HID xenon bulbs before, my last car was just regular normal bulbs that when they blew, they blew and that was that.

However in my 2008 D3, I'm having a weird issue since I got it:

If I start the car and the lights come on (if its dark enough out!) then the headlights work fine. However, if I turn off the lights then put them back on, say if i stop at a shop, park up then get back in and restart the engine - most often than not the near side headlight does not come on anymore and the dash screams an alert saying the bulb is out.

But, this is the thing... if i keep switching the headlights off and on, eventually I get the bulb back on, and the bulb warning thing on the dash obviously then disappears.

So never having had D2S HID bulbs before - is this normal behaviour when a bulb is going? Or is it the same as my old standard bulbs on an old BMW, where if it was the bulb that was out - then truly the bulb would never come back on again.... if so, what could be causing this?

Anyone else experienced this?

Passenger side, 2008 3.0 TDI D3

snapdragon · #2 3rd January 2014, 04:46 PM

I have read, (maybe on here) that if you crouch in front of the defective light in the dark and get someone to turn them on, if you see a spark flash at the moment they are turned on inside the unlit bulb, then it is probably the bulb that is kaput, if no spark, maybe the ignitor. It is the ionisation 28,000V spark that the ignitor sends to ionise the Xenon gas and make it conductive so that the normal 90v supply will travel through it.

Oli18 · #3 3rd January 2014, 05:29 PM

Hey Evo,

I had the same on mine a few weeks back where i could make it come on after a few attempts. It eventually died completely and i ended up replacing them. I would replace both as a precaution (it's not expensive to buy - <£15 for a pair of D2Ss). Take a look here if you need a 'how-to'.

Oli

evo · #4 3rd January 2014, 08:07 PM

So replacing the bulbs fixed this for you? No need to mess with any of the rest of the assembly, igniter etc?

I love how you say it was pretty easy to replace - my old BMW was easy to replace, but I'm hearing horror stories of how I have to pull off wheels and all sorts to change a bulb on this car lol!