VCDS Tweaks.
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- headlight switch vcds
I remember seeing in VCDS an option to insert or remove the option to disable the DRLs in the MFD so it is possible on the T6, just not the default
That's a common function for fog and reversing lights to have. Fog lights illuminate out to side aswell as the front, so if your about to turn the steering left or right while going backwards, it's ment to illuminate any hazards that maybe on either side of you.
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This is byte 12 bit 1 but unfortunately it doesn't enable extra options in the dash(yet
)
You can easily deactivate it by unticking bit 3 in Byte 21.
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.
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.
This has got me thinking......for those that are converting from H4 to H7 (or the aftermarket options), to keep dipped on with mains, in byte 22:
H4 - bit 2 is '1' and bit 1 is '0'
H7 - bit 2 is '0' and bit 1 is '1'
Hence 6C becomes 6A, CC becomes CA and in my case 6D became 6B
H4 - bit 2 is '1' and bit 1 is '0'
H7 - bit 2 is '0' and bit 1 is '1'
Hence 6C becomes 6A, CC becomes CA and in my case 6D became 6B
This is weird, I had twin H7 and in my case I had
bit 1 = 0 and bit 2 = 0 for Byte 22.
Yes bit 1 should be 0 for H7
This is the byte that reads ‘disable low beam when high beam active’ or words to that effect so it has to be disabled and as there’s no tick box for it reducing the code by a value of two will have that effect (remember it starts from bit 0 so bit 1 is the second bit therefore a value of two )
This is the byte that reads ‘disable low beam when high beam active’ or words to that effect so it has to be disabled and as there’s no tick box for it reducing the code by a value of two will have that effect (remember it starts from bit 0 so bit 1 is the second bit therefore a value of two )
Each 0 or 1 is a single bit, the smallest piece of information that can be stored and they count from right to left.
- For example, 1101
-- bit 0 = 1
-- bit 1 = 0
-- bit 2 = 1
-- bit 3 = 1
These are grouped in to bytes, which are 8 bits long, so 0000000 is a single byte.
As you can imagine, big number stored in binary are very confusing for humans to read, so instead we represent them in hexadecimal (base16) instead. This is a way to represent 0-15 with a single character, so it's 0 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F.
This means each byte is now just two characters, such as FF or 10. Be warned, the second one isn't actually 10, it's 16 in base10 or 00010000 in base2
- For example, 1101
-- bit 0 = 1
-- bit 1 = 0
-- bit 2 = 1
-- bit 3 = 1
These are grouped in to bytes, which are 8 bits long, so 0000000 is a single byte.
As you can imagine, big number stored in binary are very confusing for humans to read, so instead we represent them in hexadecimal (base16) instead. This is a way to represent 0-15 with a single character, so it's 0 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F.
This means each byte is now just two characters, such as FF or 10. Be warned, the second one isn't actually 10, it's 16 in base10 or 00010000 in base2
In thread https://www.t6forum.com/threads/vcds-codes-list.4851/#post-76338 we have the following about Byte 22
The Bit 1 is undefined/unknown and Bit 2 is the bit in question controlling whether low and main beams both can be on simultaneously.
A thing about mathematics in binary. In general setting/clearing single bits cannot be done by adding or subtracting numbers in hex or decimal.
Extreme example:
8 (hex/dec) – 2 (hex/dec) = 6 (hex/dec) but as actual binary numbers are
1000 (bin) – 0010 (bin) = 0110 (bin),
so instead of clearing bit 1 (which already was 0), we actually reversed bits 3, 2, 1 (1000->0110)
I think that in this case (H4/H7 headlight swap) just accidentally also the correct bit (bit 2) was changed and changing the bit 1 just didn’t hurt us. This worked because bit 1 happened to be 0 so the subtraction carried the change over also to bit 2. I am happy to stand corrected on this.
- Byte 22 Bit 0 Light reduction / evaluation Light switch (LDS) Position 0
- Byte 22 Bit 1 unknown
- Byte 22 Bit 2 Low beam inactive with main beam active
- Byte 22 Bit 3 Display daytime running light active / installed
- Byte 22 Bit 4 Shut-off of rear fog lights (NSL) with luggage compartment open
- Byte 22 Bit 5 Assistent Driving Light (ADL) active
- Byte 22 Bit 6 Interlock Display (Clutch Message) in Instrument Cluster active
The Bit 1 is undefined/unknown and Bit 2 is the bit in question controlling whether low and main beams both can be on simultaneously.
A thing about mathematics in binary. In general setting/clearing single bits cannot be done by adding or subtracting numbers in hex or decimal.
Extreme example:
8 (hex/dec) – 2 (hex/dec) = 6 (hex/dec) but as actual binary numbers are
1000 (bin) – 0010 (bin) = 0110 (bin),
so instead of clearing bit 1 (which already was 0), we actually reversed bits 3, 2, 1 (1000->0110)
I think that in this case (H4/H7 headlight swap) just accidentally also the correct bit (bit 2) was changed and changing the bit 1 just didn’t hurt us. This worked because bit 1 happened to be 0 so the subtraction carried the change over also to bit 2. I am happy to stand corrected on this.
