YAY!!!

it works.
i'm not sure what just happened. the fella read the code of my secondhand abs unit that is fitted to the car. this came up as being for the wrong vehicle. he cleared the abs ecu memory, plugged my old abs ecu in, read the original fault on that (03604) and transrefed that onto the new ecu. he then cleared that off the new ecu and bingo. £ 35 .

he says it's very rare for mk3's to have abs unit problems.