thanks for your responses,the fault i have is the abs is coming on at low speed braking,no stored codes & with live data on road test all wheel sensors appear to work ok,however comms drops out above20mph , thats with 3 machines,the trouble is the fault occurs when you go above 30 mph! very frustrating,next step i guess is to scope sensors, i also found engine ecu drowning in the wiper scuttle,dried that out , looking at wiring diag looks like engine ecu uses speed signal from abs unit so have to be sure that is not corrupt, read alot about these in archives,sounds like it could just be relucter on 1 wheel bearing,having car back in next week,should the abs comms drop out above 20 mph, if so thats pretty useless data!your thoughts?