Some C4 quattro ABS controller Part Numbers

[UrS4boy]

I did this for someone on another UrS forum so I thought I would share it here for future searches. Sorry, I don't know why there are differences other than the 92s had an ABS defeat switch and the later UrS6s had EDL (so the controller had to be more sophisticated):

1992

Manual transmission: 857907379D (we know the 92 UrS4s had an ABS defeat switch, subsequently deleted in 93 and beyond)

Automatic: 441907379

1993:

Manual transmission: 4A0907379
Automatic: 4A0907379D


1994:

Manual transmission: 4A0907379
Automatic: 4A0907379D


1995 (appears to be an EDL breakpoint at VIN SN 100000):

Manual to VIN SN 100000: 4D0907379F
Manual after VIN SN 100000: 4D0907379K

Automatic to VIN SN 100000: 4D0907379J
Automatic after VIN SN 100000: 4D0907379L

1996 (now we have EDL for sure):

Manual: 4D0907379K
Automatic: 4D0907379L

1997 (with EDL):

Manual: 4D0907379K
Automatic: 4D0907379L

1998 C4 Avants (with EDL):

Manual: 4D0907379K
Automatic: 4D0907379L

Hope that helps. (Note: Ill 927-00 in the various years contains the answers)

[Zoig]

What could be the difference between Manual and Automatic car ABS units? Some extra outputs for the Gearbox control unit?

[RichLV]

Also, pre-93 units are not visible or diagnostable via VCDS/VAG-COM. And that's very annoying.

[A1QSHIP]

Auto Vs Manual

What could be the difference between Manual and Automatic car ABS units? Some extra outputs for the Gearbox control unit?

Yes.

[UrS4boy]

What could be the difference between Manual and Automatic car ABS units? Some extra outputs for the Gearbox control unit?

Checking some wiring diagrams, for a 1995 A6Q automatic there are 4 wires connecting the ABS Control Module to the transmission control unit (TCU). These four wires are absent in a similar diagram for a 1993 C4 manual.

ABS T35/5 Grey/Violet to TCU Pin 11
ABS T35/6 White/Green to TCU Pin 12
ABS T35/7 White/Violet to TCU Pin 48 (?)
ABS T35/23 Violet/Black to TCU Pin 30