Search an find the OBD connector.
https://www.google.de/search?q=jaguar+2003+obd&client=firefox-b&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwiJ4Li01f7TAhUCBSwKHRHxCUoQsAQIJQ&biw=1536&bih=746
connect your MaxiSys and go to body and there you should read the codes and find the ABS error.Erase it and be happy.
Greetings Mathias