Still no brakes - ARRRRRGH!

I'm thinking a stuck valve in the abs modulator. This can happen if the correct procedure isn't followed when the pads are charged.

Hasn't there been a previous thread stressing the fact that the caliper pistons must not be pressed back into the caliper unless the bleed nipple has been opened, as damage can be caused to the abs modulator ???

So to recap

Car had warped discs, 3 faulty abs sensors (3 open circuit zero ohms) and one 1.5 ohms? Do you meam 1500 ohms or 1.5 k ohms? If not that one is faulty too...

Apart from the work you have done, does the braking system look like its been worked on before?

Maybe its been butchered by someone? Has some one attempted a shuttle valve bypass on the abs like what they do on discos...

Sounds like someones been messing trying to get rid of the amigos for mot purposes. ...

Hi, this looks a bit like the ABS block maybe sticking valve or trapped air. If it was on a Ford I think they have a special tool to bleed the ABS. When you pushed the caliper pistons back you are reverse bleeding the system back to the master cylinder via the ABS block - this is not allowed so to avoid this situation you should release the relative bleed nipple to allow the brake fluid an escape route instead. We've all eased brake pads back and got away with it but this time maybe not.
If everything else is right then you are left with the ABS block.

Recap - initially car braking fine just pedal little bit soggy - pads/discs change - nipples were rotten so pushed pistons in slowly. Thereafter all the probs occurred.
My main concern is - a servo has direct link to m/cyl via push rod - whether or not there is vacumm there is a pedal movement directly acting at the m/cyl via rod in servo - correct? So if the pedal pumps hard with no drooping (excuse the pun) when engine off it means the m/cyl is pressurised and brakes applied with no leaks - correct? - start engine: then pedal is pushed with vac assist but goes straight to floor - should it not be the case that when pedal is at floor the servo pin has pushed the m/cyl piston to it's max stroke under compression and again the brakes should be applied? And as no fluid is leaking and the m/cyl does not appear to be leaking back into servo - where then is the pressure of fluid from the m/cyl going or not going? The abs unit should be working on the manual bypass as shown in the RAVE diagram. Does anyone had a full understanding of the ATE 20 ABS unit in operation that might shed some light on this?

Might be worth disconecting the abs connector from the unit, start the engine and see if you get your brakes back.