Thanks Philip. Interesting thread but there are four parts to the whole ABS system ..

1. The main actuator part that activates the brakes (when pedal pressed).
2. The pump unit with accumulator that pumps up the pressure to some 2,000psi
3. The valve block that will pulsate the brakes when wheel slip is detected.
4. The ECU.

Unfortunately it is 1.) where I am sure I have the problem.