Auto light sensitivity

marty NCL

Member
T6 Pro
Hello all.
Has anyone else had the minor annoyance of auto lights being indecisive?
I often find that minor changes to light, even just cloud cover, when driving in conditions that I would consider still very bright, will cause the auto headlights to switch to dipped beam.

Is there a value in vcds that can be modified for the sensitivity?

Any help much appreciated,
Marty.
 
This has been talked about before and I'm pretty sure there's nothing that can be changed.

One thing that they do (which is good practice) is to turn the headlights on when there is low sun behind you. If there is sufficient difference in the light picked up by the front and rear facing sensors, it might think that the headlights are required, when in reality they aren't
 
Why can't they just be on, front and rear at all times? I can't see any downside to been highly visible at all times. How many times have you seen some numpty driving at night with only the front LEDS on, and on a motorway in a heavy mist or fog or rain, with no rear lights on?
 
Why can't they just be on, front and rear at all times? I can't see any downside to been highly visible at all times. How many times have you seen some numpty driving at night with only the front LEDS on, and on a motorway in a heavy mist or fog or rain, with no rear lights on?

I wondered this, both my Volvo and my BMW are always on and just turn off when you turn the car off, easy as pie and like you say you get seen better and you’ll never forget to turn your lights on
 
How many times have you seen some numpty driving at night with only the front LEDS on, and on a motorway in a heavy mist or fog or rain, with no rear lights on?

I see this every single day without fail.
 
As said above, this has been discussed before and I agree, they are extremely over-sensitive.
I've resorted to not using the auto lights and turning them on manually like we used to do in the olden days.
I have however coded my rear lights to be on permanently with OBDEleven and my van has factory LED's so the front DRL's are very bright.
 
I tried to search, but must have not looked hard enough.

I've done the same "Scandinavian DRL" rears always on. Might follow your lead, and also revert to the antique method of manual switching!

Must remember to switch back to auto for CH/LH though. I know I will be scratching my head one day soon, guessing why they aren't working!
 
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There is an option in Carista for this, you can tweak lux levels.
 
There is an option in Carista for this, you can tweak lux levels.
Interesting!
I have never used carista... I would be curious to know if there is any way of telling which module or bit/byte it was modifying?
 
Interesting!
I have never used carista... I would be curious to know if there is any way of telling which module or bit/byte it was modifying?

I had a look and unfortunately it does indicate that, just gives me the option to tweak the lux levels/numbers.
 
I had a look and unfortunately it does indicate that, just gives me the option to tweak the lux levels/numbers.
Have you played with this option?
If this is indeed a successful fix, it will make me a happy chappy!

Anyone in the north east with carista?

I'm happy to compare my scans before and after to identify which values it is looking at. It may help other users aswell.
 
Have you played with this option?
If this is indeed a successful fix, it will make me a happy chappy!

Anyone in the north east with carista?

I'm happy to compare my scans before and after to identify which values it is looking at. It may help other users aswell.
I did initially, made a right mess out of it, forgot to take a screen shot of the original values. Then I scanned my neighbor's new VW Passat with auto lights to get his values and then reapply them on my van. I also didn't want main lights coming on too soon either.
 
@marty NCL Is your van T6?
I believe @EdH has T6.1
Electronics on T6 and T6.1 are different, incompatible with each others.
 
Yeah I'm in a T6... Nevermind!

Not the end of the world, just a minor niggle that it switches between on and off quite a lot.

I think I'm going to set the nav always in dark mode. The screen switching was probably one of the biggest problems, so next best solution.

Thanks to all for the help!
 
Is there a value in vcds that can be modified for the sensitivity?
Yes, there is. However, the VCDS decodes suggest that the other options would work wrong way. Anyways, I haven't seen anyone verifying those, yet ;)
T6 sensor can be found in VCDS under 09-Central Electrics as a submodule. See below as from factory.
1653943257899.png
 
Another interesting one to experiment on the subject would be RLS byte 1. In the VCDS are documented only those values that actually exist in VW production (possibly even only on T6).

However, even just these two documented codings occupy already bits 7, 5, 3. Thus, one could assume that there could be other combinations available as well - implemented when the unit was designed to allow easy adoption later in production on different platforms/windscreens...

1669452267266.png

Obvious ones to try would be "F8" and "00" to see if they were even accepted - these two would be the max and min by using the upper five bits already allocated by two documented codings (1000 0000 & 0010 1000).

The new proposed values would be above and below current ones, so assuming correction scaling would be have a logical behaviour there might be a way to tune sensitivity up or down... possibly with some interesting side effects :whistle:
 
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