Xenon headlights are failing

[norberto]

Hi,

My Megane II xenon headlights have been failing for some time. The symptom resembles neon bulbs failing, I mean, the light seems to flicker sometimes.

This doesn't happen every single time. It happens randomly, so it is hard to show it at the dealer.

The left headlight seems to exhibit this problem more often than the right one.

Does anyone have the same problem as I? How did you solve it?

Best regards,
Norberto

[cactusbob]

Does it flicker when you start moving off?

[petesafc]

Sounds like a dodgy earth? Is everything connected ok?

[norberto]

Hi,

cactusbob, it does usually flicker when I start moving, although there are times when it flickers even if the car is stopped, so there's no pattern here.

petesafc, what do you mean by "dodgy earth", are you talking about the electrical ground?

I disassembled the headlights last December at the dealer shop in order to switch the ballasts (the left went to the right headlight, and vice versa). Unfortunately this didn't help me on figuring out the problem, as the left headlight still fails, and so the right one, exactly the way it used to fail (the left fails more often than the right one).

Before disassembling the headlights I was hoping that the problem was just a loosen connector, but although I missed out something, that doesn't seem to be the problem.

[petesafc]

Yes by earth i meant "ground" connection. I had an indicator go off and just twisted the bulb holder and it came back on! So i assumed bad earth.

[Penguin]

Hi all,
I have just brought my wife's Megane II back to our local dealer again for yet another failed Xenon bulb. I was not a happy camper. Garage costs here in Switzerland resemble a dental appointment in the UK and we were told that they had 'fixed' this problem before. The dealer then just admitted that the regulator to the bulbs surges and that the problem is a common one. To complicate matters, they changed the regulator at our last visit... Now they have agreed to a methodical tracing of the problem.
Anyone else have this 'common' problem?
We are most happy otherwise with the car. We wanted a family runabout with motorway ability (i.e. happy at 160 km/h for an hour or so, Germany is on our doorstep) and it really delivers. However, a bulb failing every two months is bloody annoying.

[MéganeDynamique]

I'm looking to add the xenon units in place of my regular halogen ones. Are the connections the same?

[davelowe]

If the circuit is anything like a fluorescent tube, then there should be a ballast that is basically a current limiting device. It allows momentary high currents when the arc is first struck, then, since the bulbs are essentially unlimited in terms of current consumption, it should then develop an internal resistance to prevent the bulbs from blowing. If faulty the bulbs will essentially overheat.

This is somewhat unrelated, but when I was designing a colour corrected reference display box for a photographic society I found all this out and got hold of a £30 electronic ballast that incorporated an invertor and switching technology which removed any flicker (around 1kHz) and would operate at a wide variety of voltages. Might be worth a look..