You said you checked the relays under the dash? all 3? How do you check them mate?

I've checked all 3 fuses under there (clipped to the relays) and none of them are blown.

Which connector is the power? Is it the 2pin one that goes into the brake resivour that holds the brake fluid?

And where's the connector for the pressure switch?

Sorry for all the questions

Mine is doing the following:
Sometimes after/while pressing the brakes, and sometimes while just driving the ABS light and handbrake light come on for 5s then go out. When they come on, and go out, I can hear the relay(s) clicking! The pedal is rock hard too