VCDS Tweaks.

Not sure I agree with that, my understanding is the each Byte is split in half and the second digit represents the first four bits
Bit 0 carries a value of 1
Bit 1 carries a value of 2
Bit 2 carries a value of 4
Bit 3 carries a value of 8
So reducing the value by 2 can only change bit 1

There is no tick box for bit 1 so it has to be changed manually
 
Im nor sure how relevant this is right now.
But I used this video when refreshing my hexadecimal calculations.
It also shows why changing bit 1 changes the value by 2.
 
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Good reference ed but the point I was making is that the byte is split in half so it 1,2,4,8 then 1,2,4,8 it doesn’t go to 16,32 ......
 
Pauly said:
Not sure I agree with that, my understanding is the each Byte is split in half and the second digit represents the first four bits
Bit 0 carries a value of 1
Bit 1 carries a value of 2
Bit 2 carries a value of 4
Bit 3 carries a value of 8
So reducing the value by 2 can only change bit 1

There is no tick box for bit 1 so it has to be changed manually
Click to expand...
Yes, correct - it changes the value but as we want to set/clear individual bits (in certain position) this subtraction works correctly only if bit 1 would have been "1" but as it happens to be "0" which means we are subtracting "0"-"1" but we can't go to down to "-1" but have to "borrow" from next bit , from bit 2. The same happens with decimal numbers, for example, 1000-2=0998, where in the result there are no digits (0..9) that are remaining in their original value in their original position.

By the way, just went out to check how this works with factory LEDs. The full byte 22 in mine is "79"="0111 1001". So in this case the significant lower half is "9".

Original "9"=1001, replaced with "D"=1101, (setting only bit 2!, others remain as they were) and now I have only either dipped or high beam on (not both). Looks very weird as the dipped and high beams are normally "stacked" on top of each other and now I'm missing the low part :eek:. As a side effect bulb failure on dash was triggered but that cleared after returning the "1001" setting.

(If I had done it by subtracting hex/dec numbers 9-2 = 7 I would have got "0111" which would have resulted most likely quite unpredictable results by turning off bit 3 (Display daytime running light active/installed). I didn't dare to try that) o_O Edit: grayed out because irrelevant in the context - have to careful which way bits are and which way to modify: setting or clearing a bit.

And yes full byte has be to entered manually - so in the above I had to replace "79" with "7D", and then return the settings by entering "79". Actually there is a helping tool in the VCDS to tick all the bits individually (@Loz 's post above) but I think the tool still needs some polishing.
 
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I see what your saying but trying to take 2 away from a code that doesn’t have bit 1 active is kind of pointless and of course it doesn’t work

You don’t have H7 lights so your results are not comparable to a vehicle that does
Each bit/byte does not share a common purpose across all vehicles, for an example there is a particular pin on the BCM that goes to your headlights as you have LED but on a PV with barn door the exact same pin goes to the rear doors and activates deadlocking
Each output of the BCM does not have a defined finite function and can vary between models as can the coding, depending on what setting you have in Byte 18 (for example) will alter what happens when you change other bytes etc etc
 
Yes, agreed. In my case it was just a curiosity if the LEDs do the same. It really doesn't make any sense with them. And, as you mentioned, unfortunately there are loads of things that eventually depend on actual configuration.

Actually my point was that I think the correct one to manipulate is bit 2 (not bit 1), so actually subtracting by 4 should give the same result :unsure:.
 
To complement @Robert 's verified tweaks earlier in this thread, here two more verified from VCDS codes list

Early T6's (up to some point year 2017) seem to leave their parking lights on if light switch is "ON" and ignition key is removed.
Light_sw_2.jpg Light_sw_warning_3.jpg
To make that go away and turn parking lights OFF when ignition key is removed (no need to turn light switch off):
Byte 24 Bit 0: when ticked ("1") Parking light OFF with low beam and S-contact OFF (Standlicht AUS bei Abblendlicht und S-Kontakt AUS)​

-------

To turn tail lights ON with DRL (of course needs to have DRL's activated, otherwise just parking lights on when ignition on):
Byte 12 Bit 0: when ticked Parking Lights ON with "Terminal 15 ON"​
 
509CC2B7-5B29-43A7-828E-22AD4F651290.jpeg
Robert said:
You have to use alternative view in the long coding (LCode 2) to see the tick boxes for all 8 bits in each Byte and then tick bit 4 & bit 7 in Byte 23.
This is the extra coding I have worked out myself and it is not documented by VCDS and I am afraid it won't be included in the next update.
This mod should work with all types of head lapms (H4, twin H7 or LED) but I have tested these on my LED retrofit only.
Click to expand...


I don’t seen to be able to find the tick boxes in byte 23.
 
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Robert said:
As per your screenshot click on LCode2 and then all check boxes for all 8 bits (within each Byte) will show up for you.
Click to expand...
Thanks, just tried that and it just flashes up for a split second then goes back to the above pic, I've managed to work it out just with binary numbers. Maybe it because I have the latest software as you mentioned before?
 
Does anybody know if we can enable typing on discover media while driving?
I have passengers who normally type the addresses but they cant enter addresses or lookup contacts while the van is moving. If I stop at lights or where ever then the keyboard becomes active and when I start moving, I get a message at the top of the screen and the keyboard disables again. So annoying
 
Yes, you can. Use VCDS and go to adaptation in your media unit and adjust max speed input limit to 150 km/h.
 
I had a look at adaptions in 5f but there are some many different items to choose from. Would you be able to give me a bit more information about which address I have to change?
 
Adjusting VCDS options will that upset any VW warranty when you next visit or a problem crops up? Mainly the one changing it to show MPH in large on dash?
 
craigblues said:
Adjusting VCDS options will that upset any VW warranty when you next visit or a problem crops up? Mainly the one changing it to show MPH in large on dash?
Click to expand...
no, the worst thing that can happen is they do a software update and change your setting back without telling you..
 
Agree with the above, VW reset my coding changes once (after discussing it with me) as they were diagnosing a fault that they thought may have been software related so changed it all back to stock for the repair and i reinstated when they returned it
 
Is it just me or does the front park sensors only work in reverse/ once been in reverse? If i drive forward into a space they dont seem to come on.
I need to look at that in VCDS.
 
PetroHeed said:
Is it just me or does the front park sensors only work in reverse/ once been in reverse? If i drive forward into a space they dont seem to come on.
I need to look at that in VCDS.
Click to expand...
Yes that’s how they’re meant to be. Haven’t seen anyway of changing it in VCDS
 
PetroHeed said:
Is it just me or does the front park sensors only work in reverse/ once been in reverse? If i drive forward into a space they dont seem to come on.
I need to look at that in VCDS.
Click to expand...

You can also press the button on the dash to activate them, if you are doing forward parking only.
 
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