Diff lock to ABS connection?

[A1QSHIP]

I have seen the 3-channel to 4-channel ABS changes throughout the European car history. Mercedes Benz, Porsche, Audi, BMW all started with 3-channel & later adapted 4-channel systems. This came about in most manufactures from 1994 to 1996 that used the Bosch ABS systems. The advent of the 4-channel ABS came about with the incorporation of traction control & stability control features into the ABS systems. The Audi UrS6 got the 4-channel ABS for the late in year model 1995s. Rest of world would call this a 1996 model, after 07/95 date of manufacture for North America are referred to as 1995.5. In these vehicles the diff lock was discontinued & both front & rear wheel slip (yes) at low speeds was controlled by pulsating the brake for the slipping wheel. This is referred to as EDL so now we have a ABS/EDL control module. So the repair manual states that EDL operates "up to a speed of 40km/h (25mph)".

HTH, Chris

[domas]

I have seen the 3-channel to 4-channel ABS changes throughout the European car history. Mercedes Benz, Porsche, Audi, BMW all started with 3-channel & later adapted 4-channel systems. This came about in most manufactures from 1994 to 1996 that used the Bosch ABS systems. The advent of the 4-channel ABS came about with the incorporation of traction control & stability control features into the ABS systems. The Audi UrS6 got the 4-channel ABS for the late in year model 1995s. Rest of world would call this a 1996 model, after 07/95 date of manufacture for North America are referred to as 1995.5. In these vehicles the diff lock was discontinued & both front & rear wheel slip (yes) at low speeds was controlled by pulsating the brake for the slipping wheel. This is referred to as EDL so now we have a ABS/EDL control module. So the repair manual states that EDL operates "up to a speed of 40km/h (25mph)".

HTH, Chris

Sorry, It does not help actually as those as well known facts I am pointing towards another question of: WHY QUATTROS HAVE RECEIVED A 4 CHANNEL ABS MUCH LATER THAN FWD CARS
The good example of my question is: m.y. 1988 b3 chasis FWD had a VAG COM friendly 4 channel abs while the same year and later quattro model b3 and c3 cars had non-vag com friendly 3 channel abs.
The question still ra

[Glen Chamberlain]

Hi Guys,
Firstly I'd like to say that the new (used) ABS ECU arrived today matching the exact part number this time and has fixed the problem. Now no more ABS light [emoji106]

Secondly I'd like to thank everyone who has helped me through this thread, all tips, advice and comments have been helpful in fixing this issue.

Thanks![emoji1]