ABS system change/upgrade

[john881000]

Hi all

I know this isnt a S2 QUESTION ,but,i hope the group concenses,can help me out

My Audi 90 quattro is being upgraded,with parts i been saving,car is nearly completely stripped out,due doing the heater matrix,but upon checking certain items i found my ABS pump is dead/finished.....couldnt get light to go out........replaced CV joints, swopped ABS sensors with known good ones(used spare hub housings off friends car).....checked wiring out no breaks found....no unusal high resistances
MY QUESTION
could i use a later ABS pump, modifing the plug wiring as well as adding wiring to have diagnois cabablities.......( sorry for rotten spelling),i still want to have the switch on dash,to disable ABS if needed

any thought would be great...

thanxs
john

[Pirvu Eugen]

are you sure the pump is dead? have you checked all the valves from it and the relay?
the fuse on top?

[john881000]

Testin

Hi mate


I had a friend,who an VW/Audi auto sparky work things over with me,,,,,he did all the checks i was helping probing necessary wiring..........he checked the usual items ,too...he had some relys from car checked said all ok

i first thought it was cv joint pick up rings corroded( they where not perfect),replaced them with better spares.........swopped ABS sensors,enven dash clocks.............still comes on...........and hard pedal as if no servo working( hasnt got the later bomb)...........but the servo seems to work ....

only thing i could think was pump finished


cheers
john


ps wouldve perfered to be able to talk to unit via VAG 1551,thats why i was hoping to use an S2 ABS unit

[Pirvu Eugen]

The abs unit has nothing to do with the servo... or bomb...
you need to check the sensors from the wheels for resistance, the relay with the 10 amps fuse on top, the 12 volt wire from the alternator, and the resistance from the valves at the unit. iff you need the wiring diagram from the 3B powered S2..tell me.
All the best!

[mcandmar]

I would love to know this myself, the ABS on my cq20v has packed in and cannot figure out where the problem is. I do know the CV joints and sensors are working so suspect pump or ecu.

As for later cars, haven't looked at it yet but a disable switch has to be easy to fit, if you think about it pressing the diff lock switch turns the ABS off so there has to be a single wire from the diff lock switch you can wire into. Or just kill the power to the control unit.