H7 Headlamp - W21W DRL Bulb Issue. Be Aware

Dieseldonkey

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I'd been having an intermittent fault with the off side DRL for a while. As soon as I put my fingers on the bulb holder, it would turn back on for a short time. However, eventually it packed up altogether. So I removed it and discovered this....

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The contacts were blackened and the plastic around them had melted. So off I went to the dealer with bulb and holder in hand.

After having to justify to the service receptionist why I'd dared to interfere with it, by removing it myself, (as per the owners manual), she took it through to the workshop for a technician to look at.

Back she came. 'This is normal. There's nothing wrong with it apart from a mark on the bulb'. She said.

There was a response from my eyebrows. They elevated to a height that would have given Hilo a run for their money. I held the bulb aloft in the direction of the vast showroom windows and gazed at it. Lets just say, De Beers would have been proud of the clarity this thing had. o_O

Request to speak directly to Mechanic.

Denied.

Assess alternative options.....

1) Start speaking loudly so the potential customers can hear and make grossly exaggerated claims about the number of followers I have on InstaGoogleTweetFace. :mad:

2) Burst into tears, start sucking my thumb and cradle my sock monkey like it's a baby.:cry:

(It really shouldn't be this hard).

I decided on the third option. Yet to master Jedi mind control, so I set about trying hypnotise receptionist. Quoting ohms laws and describing the relationship between electrical resistance and heat seemed to do the trick. (Well I certainly saw her eyes glaze over).:sleep:

So she agreed that they would take the van in for a look. Sadly, her trance like state appeared to be not that deep. She was still compos mentis enough to state that an 86 quid diagnostic fee may apply. I followed this up with a sarcastic laugh and words along the lines of NOT ON YOUR NELLY, will that be happening.

Anyway, next day they took the van in. A couple of hours after I dropped it off, I got a call to say that a Technician had looked at it and he agreed with me. It was faulty. Hooray! (Presumably, this Technician wasn't the apprentice from the day before). Indeed he also discovered that VW are aware of this issue and had published an advisory notice to their dealers about fixing it.

Result. So I tried to find out what the fix was when I got the van back. Didn't get the chance to speak to the technician, but the receptionist explained that the bulb holder and some wiring on both sides had been replaced. I'm hoping this includes the contacts on the headlight unit itself.

So if anyone else gets this issue with their H7s, don't let your dealer fob you off. ;)
 
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Is it just the heat from the bulb that has melted the bulb holder?

I’ve got Osram LEDs in my H7 DRLs. May pop one out and have a look to see how they’re fairing.
 
Looks like a prime case for an led replacement
 
Yeah, soon after you coded mine, I changed them for Osrams, and they they give out about the same amount of light, for 3w a side. Nice 6000k colour too.
 
I'd agree with @Loz conclusion on what's causing it. The bulbs are branded Toshiba, so as I've never changed them, I'm guessing they're original factory fit.

I know in reality that there are brighter, whiter, more efficient LED bulbs out there. But I've yet to find a W21W LED bulb thats type approved and E marked.

I'd hate to be involved in a prang and the insurance company wriggle off the hook on a pay out because they've clocked the bulbs. 'Our client didnt see or was dazzled by your on coming van'. That type of scenario. That's the only thing that's stopped me going down this route.

In saying that, I'm also keen that the sodding thing doesnt catch fire. Suddenly the thought of just 3 watts going across those contacts, as opposed to 21, has become quite appealing.
 
That is a concern!

I was thinking of swapping my shite standard H4's for OEM H7's but this is a worry especially If I have issues down the line.
I can't see VW being so accommodating if they have been done as an upgrade.
 
I see your point, but the parts are warrantied against manufacturing defects, so should be covered I’d think. The defect appears to be internally high resistance where the DRL contacts mate with the body of the reflector. I’d certainly argue that they should be covered.

If you bought a genuine tailgate spoiler and it was faulty, I’d expect that to be covered....
 
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I would certainly hope so.
You make a fair point but If they were bought on eBay and fitted by a local body shop or myself I can see a lot of wriggle room for them to cry foul!
 
Any product from VWUK carries minimum 2 year warranty but you would need proof of purchase, can’t see an eBay receipt would cut it unless it was from a proper business seller but I have had several things replaced under parts warranty
 
Been fine. I had a bulb out warning when I used to have a faulty Moll battery on the first start if it was left for a few days, but if you turned the engine off and restarted (as the voltage was up) it cleared.

I’ve had a new battery fitted and not seen the bulb warning for ages.
 
Been fine. I had a lamp out warning when I used to have a faulty Moll battery on the first start if it was left for a few days, but if you turned the engine off and restarted (as the voltage was up) it cleared.

I’ve had a new battery fitted and not seen the lamp warning for ages.
Same bulbs and exactly the same thing happened to me
 
Hi, I’ve got the ones in the black packet, with the three dots for brightness. The 6 year warrantied ones.
 
Been fine. I had a lamp out warning when I used to have a faulty Moll battery on the first start if it was left for a few days, but if you turned the engine off and restarted (as the voltage was up) it cleared.

I’ve had a new battery fitted and not seen the lamp warning for ages.

Hi
Can I ask whether you normally get any canbus or warning lights and did you have anything re-coded?

I am hoping I can just buy some, fit and they work!

Thanks in anticipation
 
With a decent starter battery, they just worked.

When the starter battery was low, I’d get a bulb out warning on first start of the day but not after.
 
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