Updating PY21W to LED DRL

[snapdragon]

I recently replaced the PY21Y incandescent (brown) DRLs for these LED-based luminaires....
http://s.dealextreme.com/search/100619


The result is superb, the lumens rating of these is better than new PY21W bulbs and they are just the right type of white, not ricey at all.

The only problem is I get a bulb warning on the DIS.

I have spent a long time playing with Central Electronics coding in VCDS to no avail. The options are to :

1) Remove the luminaries and try and squeeze a resistor and capacitor into them to fool the bulb test.

2) Find a coding or something with VCDS that disables the bulb warning,

3) I can code it for factory LED DRLs, if I do this, the sidelights then light up instead of the DRLS, they even dim at night for the LED to act as sidelights, and wink when indicating so that the LEDs don't mask the indicators. I would then somehow have to power the DRLs from the sidelight feed.

3 is my favourite option.
I hope I can swap the pins in a connector somewhere so that DRL and sidelights are swapped over, the sidelights then become redundant and the LEDs perform the function of both.

Has anyone done similar or have thoughts?

[sloss]

I want to do this as well and I see Autobulbs are saying they have a bulb that is Canbus compatible ie won't show a bulb error.

http://www.autobulbsdirect.co.uk/382...-led-bulb.html

They are out of stock of white at the moment.

Anyone know if this will work?

[limoncello]

there is many a thread on using LEDs and the canbus warning,

for the parking lights - seems it works on 2004 and below A8s, but warnings, flickering or just not working on others

mines 2005 , but i just got a couple of bulbs on ebay which specifically say they are for a 2005+ D3 Audi A8 so will be trying them out.

only thing i can think of to possibly help is to lower the percentage of the drls? take it down to 50 , clear the codes and see what happens

[snapdragon]

Originally Posted by limoncello

only thing i can think of to possibly help is to lower the percentage of the drls? take it down to 50 , clear the codes and see what happens

The later cars with standard LED DRL use the sidelight wire for DRL (as the DRL also functions as the sidelight at reduced power), so coding for that turns off our DRL and leaves the sidelight on all the time, the best bet would be to swap the wires/pins over in the connector and that would cancel the warning too.

I don't know why people sell these bulbs as having anything to do with CANBUS, it has nothing to do with this whatsoever.
If you get no errors with this Sloss, I might try it, but it says only 1W which would give error.

[sloss]

I did the sidelights, 5 Watt wedge type, using a resistor block specially made up to suit and no error on the DIS. It emulates the same current draw as the incandescent bulb so no power saving but you get the LED out the front which I like.

See Ebay item 300593415079 from Fizzmocouk.

I'm going to experiment with the DRLs soon and then the Front Fogs.....

Stew,

[sloss]

Here's a pic of the sidelights (parking lights)

Second pic shows Foglights which must go soon!

Last pic is the DLRs - had to fit resistor across the terminals to clear fault.
The resistor do run hot so I'll extend the wiring to bring the resistors outside the housing.

[notorious]

Originally Posted by snapdragon

Has anyone done similar or have thoughts?

I had these bulbs in rear lights for some time.

They are bright, but not reliable. In half a year they will literally fall apart into pieces since those 'faces' with LEDs are just glued to each other.

Haven't see hi quality LED bulbs yet. Now testing these with LEDs invented by US company called CREE. They are super bright and very good for rear lights, but I'm still concerned by assembly quality in China.

http://www.ebay.co.uk/itm/2X-1156-BA...item3ccd09ac2b

[snapdragon]

The ones I have at the moment are by HSUN, they are advertised as 810 Lumens, which is double the 21w originals.
http://www.aliexpress.com/item/2pcs-...746949907.html
$40 a pair, but these are by far the best I have tried, in that the light is very white and full spectrum like cars with OE LED DRLs. You can easily see them reflected on the back of the car in front, even in sunny weather.
The overall look is just like the W12, if not better.
I think it's important to have the side-firing LEDs to bounce off the reflector as well as the front-mounted one.
They get too hot to touch, about 85˚c when I measured them in the house.
They still throw faulty bulb errors though, so I really have to swap the wire for the sidelight wire but hate working at the back of these headlights as it's cramped.

[Daggerpie]

Thanks for the link, they sound perfect apart from throwing up the dreaded fault light. Any pointers to ones with the built in resistors??

[snapdragon]

Originally Posted by Daggerpie

Thanks for the link, they sound perfect apart from throwing up the dreaded fault light. Any pointers to ones with the built in resistors??

I don't think it's possible to make them in 1156 form factor - the 15W resistors would probably be bigger than the bulb itself.

The trouble with high output LED/SMDs is that even though they use less electricity, they get very hot with conductive heat, whereas traditional bulbs do use more electricity and are less efficient, but most of the heat is wasted as infra-red heat which is harmlessly radiated into the surroundings. That's why you will never see an LED-powered rotisserie.

The SMDs are already at their thermal design limits without the additional heat of resistors.

The new A8 LED headlamps have complex air-ducts, heat-sinks and fans inside because of the heat buildup in the high power LEDs.


The wasted heat of a halogen bulb shines out, but unhealthily builds up in the substrate in an LED.