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 Part Numbers:
SW: 4G0 907 379 G
HW: 4G0 907 379 G
Component: ESP PREMIUM H09 0250
Part Required:
4G927225B (OEM)
Procedure
- Use an interior tool to remove the leather interior trim.
- Lift MMI console by using two interior tools at the top half and pulling backwards towards you while you lift up.
- There are three tabs on the original switch that need to be released to push it from the bottom towards the top of the panel.
- Insert 4G927225B
- Reconnect connectors
- Reassemble
- Use VCDS
- Select Address 03 (ABS)
- Access authorization -> Enter Access Code 61378 or S11820
- Long Coding Helper -> Byte 8
- Use the call out below to change this byte to the proper value.
- Turn your car off and back on
- Clear DTCs via VCDS or OBD11
DO NOT JUST PASTE THE BELOW ABS CODING TO YOUR ABS CODING.
Calculating Byte 8's Value:
For our example, the original ABS long coding we'll use is:
44A70F0122E5F0804B00
4B near the end is Byte 8 (as they start at 00)
(See below table)
https://www.binaryhexconverter.com/hex-to-binary-converter
| 00 | 01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 |
| 44 | A7 | 0F | 01 | 22 | E5 | F0 | 80 | 4B | 00 |
The 8th byte in this case, 4B is binary for 01001011
By changing the first four digits to 10011011
The converted binary 10011011 to HEX is 9B
So, our new long coding would be:
44A70F0122E5F0809B00
(See below table)
https://www.binaryhexconverter.com/hex-to-binary-converter
| 00 | 01 | 02 | 03 | 04 | 05 | 06 | 07 | 08 | 09 |
| 44 | A7 | 0F | 01 | 22 | E5 | F0 | 80 | 9B | 00 |
DO NOT JUST PASTE THE ABOVE ABS CODING TO YOUR ABS CODING.