the abs light was staying on on my e30 and the abs wasnt working.
checked all sensors seem tobe ok
changed two relays in abs unit still the same
changed the abs control unit still the same
then saw a little silver relay where the glovebox is on top where the abs ecu was
so i decided to open it up
there is a small piece of wire on the side which looks the the old house fuse wire which was blown
soldered it back togeather and my abs is ok now
thanks for those people who tried to help me
many thanks hass