Auto Hold Retrofit

No need to run wires all the way to the ABS unit from the center console. All 4GX comes with this wiring factory installed. Nevertheless, note that this was done to 1AT PR code ABS module. If you have 1AS ABS module, it may still work, but it may stress your ABS unit slightly more.

Example ABS Control Unit is Part No SW: 4G0 907 379 G HW: 4G0 907 379 G Component: ESP PREMIUM H09 0250

Part Required:
4G927225B

Procedure

1.  Lift gear shift boot cover.
2.  Lift MMI console
3. Unplug parking break button connector
4. Replace existing with 4g1927225b
5. Assemble back
6. Use VCDS
   
7. Select Address 03 (ABS)
8. Access authorization -> Enter Access Code 61378
9. Coding -> Byte 8, Activate bit 4, 7 and deactivate bit 6.
   
   Now, if you use VCDS, you wouldn't be able to tick a box in long coding helper.
   
   So, you need to calculate Byte 8's HEX value!
   
   

   For example, the original ABS long coding is:

   44A70F0122E5F0804B00

   and 4B near the end is Byte 8.

   HEX 4B is Binary 01001011

   Changing bits to 10011011

   Converting binary 10011011 to HEX is 9B

   So the new long coding is:

   44A70F0122E5F0809B00

   
   https://www.binaryhexconverter.com/hex-to-binary-converter
   
   DO NOT JUST PASTE THE ABOVE ABS CODING TO YOUR ABS CODING.
   
   Enter the coding and you will get immediately a TPMS error.
   
   Just restart the ignition, clear codes and it should go away.