On the contrary - the gen 1 FSM details what fault code is generated by which specific failed component of the ABS system (leaving the gen 2 aside as it's a somewhat different system). Such brake failure is bad and conceivably caused by lack of maintenance, which seems to cause the valve(s) within the ABS unit to stick in the 'open to pump/closed to master cylinder' position (service code 13 or 14 below) which, in turn, causes a hydraulic lock back to the master cylinder.
While rear brake failure of this type is bad enough, there is a second life-threatening failure - that of the warning system itself. The ABS warning lamp goes off after the first short distance of start-up riding, falsely giving the rider feedback that the brake system is trouble-free whereas, in fact, the rear brakes have failed the test and will fail to apply but the lamp doesn't show it.
What happens if the valves in the front circuit (code 17 or 18) gets stuck? I've not seen it reported. Perhaps no-one has lived to do so.
(Links to this info were further back in this thread.)