How does Long Coding work?
{Long Coding} New models, especially those with CAN-bus based diagnostics, use the so called long coding.
A hexadecimal group of Bytes is shown, which needs to be split into its single Bytes/Bits, this will be described in the following example.
In this example we will determine how to activate the daytime running lights (DRL) in Golf 5 based Models.
The current coding from our example central electronics control module (address 09) is 008F8F020004200000120C. We split the complete coding in its single Bytes and convert them (e.g. with the Windows-Calculator - View/Scientific) back to binary values.
Byte - Number Value (hexadecimal) Value (binary)
00 00 00000000
01 8F 10001111
02 8F 10001111
03 02 00000010
04 00 00000000
05 04 00000100
06 20 00100000
07 00 00000000
08 00 00000000
09 12 00010010
10 0C 00001100
The particular byte is now split into bits the meaning of these bits is shown in the tables of OpenOBD.org.
For our example we need to look at Byte 00 Bit 3 (Note: The Bytes are counted from left to right and the bits from right to left, both starting with 0). So Byte 00 has the hexadecimal value of 00, converted to the binary system 00000000.
Bit Value Meaning
Bit 0 0 Fog Lights installed
Bit 1 0 Xenon Headlights installed
Bit 2 0 Footwell Lights installed
Bit 3 0 Daytime Running Lights (Scandinavia)
Bit 4 0 Daytime Running Lights (North America)
Bit 5 0 Assistance Driving Light & Leaving Home
Bit 6 0 Rain/Light Sensor installed
Bit 7 0 Coming-Home active
According to the tables Byte 00 Bit 3 is used for Daytime Running Lights, the Scandinavia version, our example coding shows that this bit is 0, which means that this option is inactive.
To activate the Daytime Running Lights one needs to set Byte 00 Bit 3, so the new value is 1 and the new binary value for Byte 00 becomes 00001000, converted to hexadecimal this is 08.
Finally we put all together, the rest of the coding is unchanged, only Byte 00 was changed, so we get 088F8F020004200000120C and this is what one needs to be entered in the diagnostic tool.