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Discussion Starter · #1 · (Edited)
Fellow A5 and S5 enthusiasts,

By now we all know about the "winking DRL" problem that has plagued most of us A5 owners. Audi's apparent attempt at a safety feature has caused most of us nothing but annoyance over the last several months. Some of us have even resorted to not using our turn signals as much to avoid embarrassment.

Well, the need to toss out the rules of the road in the name of vanity is gone. I have found the solution to our problems, and it's nothing but a simple VAG-COM coding! One single bit in one controller changes the behavior entirely.

Sebastian at Ross-Tech was able to supply me with the Central Electronics Module codings from a couple very early build A5/S5s, which apparently had the behavior we all have sought. This allowed me to compare to the coding in my own car's CEM, narrowing my search to just those bytes which were different.

After bravely toggling bits blindly and trying to see what difference it made to the car, I learned a great deal about controlling DRL behavior. First of all, you can make almost any lights on the car function as daytime running lights: fogs, headlamps, side markers, tail markers, LEDs, or various combinations of these. But more importantly, I uncovered the single bit that keeps the DRL on the signal side from going out.

I won't post the entire coding of my CEM here, because that only encourages folks who don't know any better to cut and paste into their own cars. And blindly transferring VW/Audi's long coding is a recipe for disaster. Rather, I will only describe the particular bit that needs changed, as that will provide all the necessary information to anyone who knows how to use the tool properly, but won't encourage others do damage to their cars.

The bit can be found at:

Module address 09 (Central Electronics)
Submodule 0 (Master Cent. Elec. box, rather than a slave module)
Byte 3 (fourth from the left)
Bit 7 (first bit from the left in the binary representation, bottom check box in the VAG-COM long coding helper).

In cars like mine that "winked" from the factory, this bit is set to 1. (My original coding for Byte 3 was 91 in hex, or 10010001 in binary). Flipping this bit to 0 (in my case, making Byte 3 read 11 in hex, or 00010001 in binary) makes the DRLs stay lit on both sides when signaling. Simple as that.

Again, I haven't posted full codings because I don't want to help anyone mess up their car. Even with this precaution, I am still posting this information on a "use at your own risk" basis. I don't see how this can do anything bad to your car, but if you choose to do this, don't look at me if it has unintended consequences.

I hope this helps all of you out. If anyone has questions about how to change their particular car's coding, I'm more than happy to assist. If anyone close by (there aren't many) wants to make use of a VAG-COM cable, I'm also happy to help.

Dave
 

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Dave, you rock!!! You should win some type of award or something for this awesome discovery! :)

Admittedly, I think I will wait for a few others in the US to try this out on their cars before I do anything to mine.

For you newbies who might be wondering what Dave is referring to by the "winking DRL", you can read more background info on this topic here.
 

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Discussion Starter · #3 ·
Thanks TX. I can understand wanting to see some other brave souls try it first. I'm happy to be a guinea pig for our awesome community.

I also thought I'd mention, in the interest of being precise, the specifics of my Central Electronics Module. Any box with the same part number, revision number, and component ID should work just fine because they're the same box with the same firmware. But if Audi decides to "fix" this loophole in the future, there may be a new part number or new revision code, and that may be the reason if this won't work in the future. If the numbers below change later on there's no guarantee we can still so this. But the cars I used for inspiration had slightly different component IDs (H19 0141 where mine is H21 0253), and it still works fine. Just saying that there are no guarantees down the road.

Here's my module data:

Code:
Part No SW: 8K0 907 063 D    HW: 8K0 907 063 D
   Component: BCM1 1.0      H21 0253  
   Revision: 05021001
 

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Dave.. I knew it wouldn't be long before we were all bearing the fruits of you getting your hands on one of these puppies! You do indeed rock! I think I can now justify getting a VAG-COM...for this and the slight bit of voice command. The windows with the fog...meh...

But this is huge!! I will actually be a safer driver because of you!

Now..about those license plate and dome light bulb LED mods... ;)
 

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Excellent bit of detective work

Hey Dave,

The community will be very grateful for you for this. Ironically, I was just telling my wife that I was going to send a "page" to the brits asking for someone to scan their vehicle - so I was delighted to see that Ross Tech helped out in the end.

I am tempted to plug in my S5 now and try it out. I need to carefully study your text first. I have heard in other forums of people blindly cuting and pasting codes only to find strange behavior like the locks don't work correctly anymore. The key is understand which bytes ONLY affect the DRLs.

Now for those of you with the wire cutters - quit slicing up that new wiring harness, and let's figure out the changes needed on the S5!
 

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Discussion Starter · #6 · (Edited)
SD, this should work fine on the S5. One of the cars I studied for the coding was an S5, the other an A5 3.0 TDI. So both cars were different from my own model, but both used the same Cent. Elec. module. All three—myself, S5, and TDI—had the same part number (8K0 907 063 D), and the S5 and TDI had the same "component ID" , even though mine was different from those two.

The point is that all of our cars, so far, seem have the same CE box. In fact, based on your screenshot in the other thread, yours has the exact same part number and component ID as mine. I can say with some certainty that you should have identical results to mine.

If you want me to be a second set of eyes to check your proposed coding change before you apply it, I'd be happy to. But just a hint: I'm looking at that screenshot, and it looks like you need to change the same "91" to "11" that I did in that code. (instead of starting 26001091..., it should start 26001011...)
 

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Here are the results on my USA 2008MY S5

Hi Dave,

Once all the hard work had been done by yourself, the rest was easy.

I changed bit 7 and verified the new coding as you suggested.

Here is the result from a few moments ago
 

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Discussion Starter · #9 · (Edited)
Dave - do you definitely recommend getting a Hex over Key cable? Will only the former dig this deep?
.
According to Ross-Tech's application chart for the A5/S5, only the HEX interfaces will work. Specifically, the HEX+CAN versions (the A5 is all CAN bus). So unfortunately, we've got to shell out for the most expensive one.

Here is the result from a few moments ago
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That's awesome. I'm so glad it worked for you.

However, my notoriety as the only B8 in North America without a winking disorder was very short-lived. :D
 

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I don't intend to hikjack the thread, but would someone explain the basics of Vag-Com? It sounds like a similar program that I use to tune my D-max (EFI-Live). However, I've never heard of VAG-COM and want to look into it. I have some experience tuning gas engines and lots of experience on D-max diesel engines (FWIW, I can spin the tires in third gear just by getting on the gas and I'm running 35" tires with an auto transmission).

It looks like Ross-Tech is the provider of Vag-Com??? So what can it do? How much? Benefits/drawbacks?

Thanx and please don't let this thread topic drift too much.
 

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Now watch for the flood of requests to borrow VAG.COM cables and software:D

So far with my S5, I had only very minor annoyances - the one that I fixed within days of getting the car was the "airbag is off" warning light. I went the very un-elegant solution and flipped the switch out of the dash, gently prised the cover off and placed black tape on the inside to mask off the light:cool:

I have also switched off the seat belt chime and been keeping an eye on fault codes from time to time.

The guys at Ross Tech are great - I hope members will reward them by purchasing a cable and software;)

ps; If you send me an PM with your email - I'll send you copies of the 4 study guides in case you don't already have them.
 

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Discussion Starter · #12 ·
One other thing I thought I'd mention...

In the thread linked to by TXcarguy above, it appears that Euro-spec B8s do all sorts of different things with their LEDs. Some dim the signal-side LED strip, some turn it off, some don't do anything. As it turns out (not surprisingly), all these things can be controlled in the module coding. Setting a different bit than I described above can make the LEDs dim to the 50% parking-light level on the signal side. Consider it like an in-between solution. However, on US-spec cars, this also causes the amber side marker to stay on all the time, as additional DRLs along with the LEDs. I suspect this is an consequence of the different headlight housings, since the Euro lamps don't have the amber marker. The coding bit that creates dim-with-signal behavior was probably not intended to be used in the US, and so in my car it has the side effect of making the amber light a DRL.

I only bring this up because people in the other thread were trying to figure out where the different observed behaviors were coming from. The side marker does not enter the equation with the fix I've posted, as evidenced by SDS5's picture. I just wanted to add that bit of trivia for anyone interested. What can I say, I'm an engineer.

Would someone explain the basics of Vag-Com?

VAG-COM is diagnostic software only, not performance tuning software like you might see advertised in the back of the car magazines. Nothing against that type of software, that's just not what VAG-COM is. It emulates the functions of the dealer diagnostic computer, so you can clear check engine lights and get real-time telemetry from vehicle systems. The most sophisticated interface cable they offer is $350, and that includes the software license. Check out http://www.ross-tech.com/ for more info, and see the special VAG-COM forums at VWvortex and AudiWorld for relevant discussions.
 

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This is great news - thanks for all your hard work.
Before I spend £250 or so (around $500) on the VAG-COM stuff, I wonder if you could tell me if the following are do-able (perhaps some other members would be interested in these features too)?
1) Have the rear lights on at the same time as the DRL's so we can drive a little longer without headlights
2) Have the instrument cluster backlights stay on a little longer too.
3) Adjust the up/down headlight alignment on my Xenons

I'm not advocating driving on DRL's in total darkness - just a little longer into the evening. It has to be said that my Xenons only light up the road about 20 feet in front of me. I tried turnning them off the other night and I can actually see farther (rear reflectors etc) on DRLs alone than I can with the Xenon's on.

Cheers - and thanks again for all your hard work
Plob
 

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Dave you just gained Hero status...fine detective work. As you say Euro spec cars behave in different ways, my LED's stay on full when indicating, but like 'Plob' I'm excited by the prospect of turning the rear lights on as DRLs. Thanks for the excellent info.
 

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Excellent, very well done!!

Did you find any way of changing the Side-Light brightneess though?? Since when the sidelights are selected the brightness isn't that of the DRLs??
 

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Hi Blade
I'd forgotten that your car didn't dim the DRLs. Perhaps its worth doing a 'Euro' model comparison to see if we can see a difference in settings.
The thing that concerns me is that we have three different levels of functionality with the DRLs:-
1) They remain on at all times - even when indicating (like yours)
2) They turn off when indicating (like Aerodave's)
3) They dim when indicating or turning on the side/headlights (like mine)

Of course, this functionality can't be acheived using one bit alone in the configuration settings - it can only be a one or a zero. This suggests that there may be other bits in the byte that have an effect here (8 bits in a byte).
If we were able to read (and share) information on these settings, we could see which bits are set differently and change their settings. I'm a bit reluctant to change any settings until I have a good idea of what these bit assignments are for (or even if we have different control units/versions).

So, the burning question has to be the one of how do we find this out? Do you have access to a VAG-COM setup and are you willing to read and share (not change) your settings?

Cheers
Plob
 

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Hi Blade
I'd forgotten that your car didn't dim the DRLs. Perhaps its worth doing a 'Euro' model comparison to see if we can see a difference in settings.
The thing that concerns me is that we have three different levels of functionality with the DRLs:-
1) They remain on at all times - even when indicating (like yours)
2) They turn off when indicating (like Aerodave's)
3) They dim when indicating or turning on the side/headlights (like mine)

Of course, this functionality can't be acheived using one bit alone in the configuration settings - it can only be a one or a zero. This suggests that there may be other bits in the byte that have an effect here (8 bits in a byte).
If we were able to read (and share) information on these settings, we could see which bits are set differently and change their settings. I'm a bit reluctant to change any settings until I have a good idea of what these bit assignments are for (or even if we have different control units/versions).

So, the burning question has to be the one of how do we find this out? Do you have access to a VAG-COM setup and are you willing to read and share (not change) your settings?

Cheers
Plob
OK Plob, I don't have access to a VAG-COM, (Despite owning a garage - Renault & Fiat) I was thinking maybe APS do, in which case surely when we go up for the mods in June they could hook up and check out the settings. I don't have a problem being a guinea pig here, I would like my rear lights on at all times and need to know that when the car goes in for service, if they update the software, I don't end up with dimming DRL's...
 

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Excellent, very well done!!

Did you find any way of changing the Side-Light brightneess though?? Since when the sidelights are selected the brightness isn't that of the DRLs??
Rab this won't matter anymore anyway, once the vag-com has been used to keep the rear lights on all the time, you can leave it on DRL in the full bright mode. I'm assuming thats the only reaosn you would turn the side lights on.

Now I don't have a clue about anything to do with VAG-COM so i'll wait for one of the UK guyz to do it then i'll get help from them to do mine.

Oh and well done Dave!! :)
 

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Dave, great work and very thorough on the explanation. When I get my car, I'll proceed. I'm usually hesitant on doing anything as I'm concerned about messing something up, but you laid it out nicely to make it easy. Thanks!
 

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Discussion Starter · #20 ·
Thanks for all the kind words guys. :D I'm just really glad to be of help to all the people that have been helping me out for the last few months. I knew somebody out there would figure it out eventually...I'm just glad we don't have to wait any longer.

I wonder if you could tell me if the following are do-able 1) Have the rear lights on at the same time as the DRL's so we can drive a little longer without headlights
2) Have the instrument cluster backlights stay on a little longer too.
3) Adjust the up/down headlight alignment on my Xenons
Number 1 is absolutely doable, as I discovered last night. You can easily have the taillights come on as DRLs, in addition to the LED strips in front. And in this mode, the LEDs would be at full brightness all the time.

I don't have answers for 2 and 3, and I don't know if anyone does right now. There's just so much undocumented in the control modules. But I'd bet that you can do #3, as there is a "Xenon Range" controller. It's likely that there is what's called an "adaptation value" that can adjust the baseline headlight level. #2 is more questionable, but since it's all based on sensors and logic, there's probably a way to manipulate that behavior. But I wouldn't swear to it.

The thing that concerns me is that we have three different levels of functionality with the DRLs. ... Of course, this functionality can't be acheived using one bit alone in the configuration settings - it can only be a one or a zero.
There is a bit for dimming, and a bit for turning off. I don't know what happens if both are set, as I haven't tried. But all possible DRL behavior described by members here can be described by three comibinations of those two bits. (0 and 0; 0 and 1; 1 and 0).
 
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