I've a '92 RRC with a dud ABS pump.

I think it's a dud because the 5 pin plug does have power but the pump silent when the ign is switched on. This indicates to me a mechanical failure. The pedal is normal but it requires temple-popping pressure to pull the beast up.

What's the State of Play? Replace? Changeover? Do Wabco do repair "kits"?