Dimming Direction in MQB's BCM

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volksautoservice

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Hi guys,

I have some questions regarding the "Leuchte" adaptation channels in the MQBs BCM.

1- I'm struggling to understand the purpose of "Dimming Direction". I mean if I would to set the FL fog lights to light up alternatively with the FL blinker I suppose I need to set it "Blinken links Dunkelphase" in one of the (A-H) and the corresponding "Dimmwert" to something like 100. So what is the purpose of setting "Dimming Direction" to "maximize" or "minimize"? What am I maximizing or minimizing :banghead:?

2- Are the A any different than B or C or... H in those channels?

3- What are the maximum "Dimmwert" value for LED and Halogen and for XENON?

4- Since "A" and "B" have the same "Dimmwert" and "Dimming Direction" (just like "C" and "D"...) why would someone set his tweak to the "B" while the "A" is already used (let's say was originally used) and had already the "Dimwert" and "Dimming Direction" in the "AB" channel already set? I mean why wouldn't he used "D" if "C" is also free? not sure if I made it clear.

5- Does the explanatory table kindly shared by DV52 here also applies to SEAT Leon lights knowing it has the Parking/DRL lights working as blinkers at the same time?

I'll be grateful for any one who might help understand these BCMs analogy and I hope I wasn't rude asking all these silly questions at once :thanks:

Cheers :thumbs:
 
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PetrolDave

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1. Minimize means if that condition is true then the lights will be NO BRIGHTER than the value, maximize means if the condition is true then the lights will be AT LEAST AS BRIGHT as the value.

2. H&G have higher priority than F&E which have higher priority than D&C which have higher priority than B&A.

3. ?

4. H&G, F&E, D&C and B&A are effectively logically OR'ed together so you can use either as per your choice, so it doesn't matter if e.g. D is used and C isn't then it has the same effect as using C and not D - it's either personal choice or maybe for VAG to keep consistent use between model variants?

5. ?
 
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DV52

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3. LED = 127
TBAx:127? I am very uncomfortable raising this question, but are you sure that this is universally the case? My very amateur observation is that there are certainly many examples where the setting 127 is possible for LEDs, however there also appears to be a not insubstantial body of evidence where LED lamp settings are restricted to 100 (just like incandescent lamps).

I'm more than happy to be convinced otherwise, but my observation of MQB admaps is that whether 127 is an acceptable maximum really depends on the actual setting in the Lasttyp channel in the Leuchte-set. For example, if the settings 34 - LED Bremsleuchten, or 38 - LED Blinkleuchten, or 41 - LED Kleinleistung, or 42 - LED dritte Bremsleuchte is used in the Lastyyp channel, the factory setting for the Dimmwert channels is invariably not greater than 100. In fact, my recollection is that Dimmwert values of 127 in Leutche-sets with these Lastyyp values,will result in a DTC (I think).

My simple assumption (based purely on a guess) has been that the phalanx of possible Lastyyp settings can be broadly divided into analogue and digital dimming control. I assume this because of the max numbers, 100 and 127 (which is really 128 if "0" is considered and is therefore hex08). It appears that incandescent settings are ALL analogue. However, I'm not sure that ALL LED settings are digital

But as I have said, I'm very nervous making such an assertion to a response by TBAx.


Don
 
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volksautoservice

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Many thanks for all your answers guys. I'm really grateful for your help.
An advanced exercise for me now is to fully understand this:
https://goo.gl/s0iIpe
:rolleyes:
 
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TBAx

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DV52: you are absolutely correct. My statement was way to undifferentiated.

It is always a mixture of Lasttyp and Dimming value and sometimes even VAG doesn‘t know when to use what. I‘ve seen scans where two identical cars (at least in regards of lights) had different dimming values (100 vs. 127) with everything else in this Leuchte group identical.
 
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