Thanks for that. The pins in the ABS leads are so deep that I can't get my multi meter prongs on them.
I have access to a proper garage code reader, by using the connector under the dash I pulled about 20 years of codes and cleared them. The round socket under the bonnet will not connect and this is the socket that reads the ABS.
Using google it appears that you cannot read the abs codes without altering the wiring on both sockets, the round socket is easy but you need pins to push through the socket under the dash and I haven't found anything suitable.
Useful link on this subject.