DRL with LEDs - disable diagnosis error

[33q]

I follow the LED DRL threads with great interest. I'd like to upgrade to really bright white lights as I do think the standard bulbs seem a little yellow. However I don't subscribe to the 'improvise, adapt and overcome' approach......well not in this case.

I have no idea how to do it personally but I really wish someone comes up with a way of changing the canbus parameters so that LED bulbs work at their nice white low power design.

[Yety]

I follow the LED DRL threads with great interest. I'd like to upgrade to really bright white lights as I do think the standard bulbs seem a little yellow. However I don't subscribe to the 'improvise, adapt and overcome' approach......well not in this case.

I have no idea how to do it personally but I really wish someone comes up with a way of changing the canbus parameters so that LED bulbs work at their nice white low power design.

 

Not wishing to cause "trouble", but why is a filament DRL deemed "not quiet right" Why should it be dazzlingly white and bright?

 

It's only a daylight running light, if you can't see the car itself then somethings wrong somewhere. I know all the arguments, but it seems a fashion thing, or a competition to get the brightest/whitess light going :think:

 

Don't get me wrong, I'm a great led fan but I'm not in favour of the ultra bright Citroen/Audi etc led DRLs. They all seem far too bright for their intended purpose and are a distraction to many eyes.

 

I like the "yellow" Yeti DRLs, better still, I'd like no DRLs at all   Call me old fashioned, but I'd prefer better driving standards and law enforcement instead of ever increasing "driver aids". People only then take advantage of them, and then new "aids" have to be introduced. 

 

OK, I am old fashioned

[g6zru]

>OK, I am old fashioned  <

No you're not! You're a discerning and considerate gentleman.   :clap: 

 

Fred

[john.errington]

Translator - no just some mistakes corrected.

 

1: the resistor you use to prevent a bulb error showing simply matches the current drawn by the LED lamp to that taken by the standard filament lamp.
"The normal P13W bulb has a cold resistance of about 2.7 to 3 ohms, when it is hot 21w at 13.6v is a current of just over 1.5A, which works out at 8ohms, so a 10ohm ballast resistor would not load the control unit any more than a P13W filament bulb." (Thanks Cropwell, saved me working it out)

 

 

2:

"but if they are not bifilar  or Ayrton-Perry wound then they would have an undesirable inductive component. This would manifest itself as an impedance at switch on as the build up of the magnetic field opposes the current.  The spike would be formed when the current is switched off as the collapsing magnetic field generates a back-emf spike. This is easily quenched with a capacitor or diode.  This back-emf pulse is more likely to damage the J519 unit."

 

There I must disagree, Cropwell. A low resistance wirewound resistor is not the same as an induction coil!  An ignition coil has a primary inductance of  8mH. The resistor has far fewer windings, and (this makes a BIG difference) does not have an iron core.   I have measured the inductance of a 10 ohm 10W wirewound and it was around 0.0012 mH. Too small to be any more significant than the inductance of the connecting wires. (it doesnt HAVE to be a coil to have inductance)

 

3 so basically as far as the control unit is concerned, there is no measurable difference between an LED lamp + resistor, and a conventional bulb.

 

And no way of "fooling" the control unit other than drawing the same amount of power as the standard bulb would consume.  Shame.

[mikep]

I put up with the light fail warning.

I spent several hours looking through the various settings in VCDS, the problem is there isn't a full programming manual out there, Ross Tech do their best but they have to approach it by reverse engineering most of the time. The same control module is used across the VAG range including a number of vehicles with LED driving lights, so all I need to do is find an appropriate vehicle and see what settings it uses and we might possibly have a solution.

Note use of word 'possibly'.

[33q]

mikep I wish you well in your search.

Keep us updated. I suspect Rosstech may sell me a unit if a solution to this holy grail is found.

[Guest Cropwell]

 

 

2:

"but if they are not bifilar  or Ayrton-Perry wound then they would have an undesirable inductive component. This would manifest itself as an impedance at switch on as the build up of the magnetic field opposes the current.  The spike would be formed when the current is switched off as the collapsing magnetic field generates a back-emf spike. This is easily quenched with a capacitor or diode.  This back-emf pulse is more likely to damage the J519 unit."

 

There I must disagree, Cropwell. A low resistance wirewound resistor is not the same as an induction coil!  An ignition coil has a primary inductance of  8mH. The resistor has far fewer windings, and (this makes a BIG difference) does not have an iron core.   I have measured the inductance of a 10 ohm 10W wirewound and it was around 0.0012 mH. Too small to be any more significant than the inductance of the connecting wires. (it doesnt HAVE to be a coil to have inductance)

 

 

 

John, I didn't say that a low val ww res was the same as an induction coil, I just said that some exhibit some inductance which would cause a back emf on switch off due to the auto-transformer effect. I agree it would be small and insignificant and most ww res's are designed to minimise inductance anyway (for example by winding both haves in opposite directions round a ferrite core).

Sherlock cited spikes at switch ON, my point was that any inductance would dampen spikes at switch on, if they appeared anywhere it would be more likely at switch OFF.

 

I have decided it is better to go into research mode and, hopefully, return with some results of interest.

 

I have done with farting about with ballast resistors, but if anyone wants to use them - go ahead, just remember they get as hot as the filament bulb they emulate, so be careful where you put them !

[Guest Cropwell]

First, to  eliminate the need for ballast resistors, you can switch the bulb failure warning setting off, or to LED on some later models, but you need VAS-PC or ODIS to do it, which are dealer tools  .

Secondly, My problem with dynamic cornering lights not working has been fixed.  It was not due to Ballast resistors on the LED DRLs. I have now initiated a complaint with Skoda UK and will put full details to the forum in due course, but for now it would be imprudent to say more.

[shrops_paul]

I don't know how you could be bothered. It's a lot if fuss for something you can't see while driving. I bet you are a daemon on interior rattles.

[Truthseeker]

Would not fancy selling a used car to Cropwell.

[freedie]

Would not fancy buying a used car from Cropwell.

[briskycat]

The normal P13W bulb has a cold resistance of about 2.7 to 3 ohms, when it is hot 21w at 13.6v is a current of just over 1.5A, which works out at 8ohms

That is a bit odd: I thought P13W implies the power of 13 and not 21 Watts...

P.S. I would not even bother but the cost of spare P13W (VAG p/n N10737301) bulbs seems unreasonably high to me.

[thingy]

Help! There are a lot of clever people on this forum (well compared to me) so PLEASE can you help?

I presume the DRLs can be switched off so as to not work with the ignition on.

 

If I install separate DRLs on a separate switch through a live fuse (after ignition on) will these be monitored through the Can-Bus?

Reason being I can then fit front & rear DRLs.

 I get my Yeti in 5-6 weeks.

 

Thanks folks.

Edited 23 December, 2013 by thingy

[33q]

I think I'd consider myself to be cautious and advise you that you risk your warranty. Ok you suggest a separate circuit but the original wiring will think the original bulb has failed and you will be no better off

[Truthseeker]

I think I'd consider myself to be cautious and advise you that you risk your warranty. Ok you suggest a separate circuit but the original wiring will think the original bulb has failed and you will be no better off

Very sound advise 33q.

 

 

Reason being I can then fit front & rear DRLs.

 

What are rear DRL's?

[kernow]

Took my Yeti in for the first service.

Did not tell them i had DRL LED bulbs fitted.

The original SuperSkoda ones.

Error only comes on if ignition is turned on and engine not started after a minute.

Came back from service with no mention and clean bill of heath

[thingy]

Thanks 33q & Truthseeker.

The handbook page 46 says how to turn off the DRLs, so that bit should not throw up a failed bulb.

 

At present I use, have fitted, truck Marker lights. They have 2 LED's and the rest of the lens is a reflector, which can be Red, White or Yellow.

White at the front & Red at the rear. I have the front & rear linked into my side lights which have been fitted on 4 different cars over the last 10+ years and, passed the MOT every time.

 

I know the law states that ANY lights fitted must comply with EU regs (also stamped as such), and a certain height from the road and equal distance from edge of vehicle and of course of equal watts.

 

I was concerned what the Can-Bus would throw up with any extra circuits, as I also need to install in-car video and speed camera detector.

I'm just planning ahead before delivery.

[john.errington]

One of my rally cars had a seriously bright main beam indicator that could not be changed. A small piece of insulating tape over the indicator did the trick! Works for the lamp fail too.
 My wife has a Golf and the "lamp fail warning" lights intermittently. Check all the bulbs - they are fine, all working, no flickering. No LEDs just conventional bulbs.  WTF???

[mikep]

Ross-Tech finally came back on this question this week, they have no knowledge of any coding to remove the error. Such a shame!

[JungleJames]

 

 

I like the "yellow" Yeti DRLs, better still, I'd like no DRLs at all

I cant see the point in DRLs at all. It doesnt help you see the car any better in daylight. All it does is give you extra bulbs to replace, hence more expense. Perhaps thats the point of it :think:

Anyway, ive switched mine off through the Amundsen because they are just a waste.

[freedie]

I'm amazed you can switch anything off (or on) through the Amundsen. How is this done please?

[Llanigraham]

I'm trying to work out how they are a waste!

[JungleJames]

I'm trying to work out how they are a waste!

Well if i can be proved wrong, then OK, but me personally, I can not see a use for them. They dont help you see anything in daylight. Well certainly no DRLs on other cars have ever helped me see thecar any better. In darkness you already have lights. So to me DRLs are just extra bulbs to blow, hence more cost, for no benefit. If i have missed anything, then im happy to be corrected, but to me personally, no benefit that i can think of so far.

[ians330]

I like the idea of leds but any advantage is lost as soon as you add a resistor. Also I was of the turn the drls off, then the thought occurred what if I have a bump the insurance company are going to ask if they were on. So they are back on

Ian

[JungleJames]

I'm amazed you can switch anything off (or on) through the Amundsen. How is this done please?

Go to car setup, and its under the 'lights' menu

 

Edit- Bare in mind thats on my Octy. Not 100% sure regarding other models

Edited 19 January, 2014 by JungleJames