Tom, it may have been different for the 59 model, but the 57 (and I know from some very hard-learned lessons) requires you to hold the suds switch in the 'return' position until the indicator light went on.  This meant the suds pump had moved enough water to trip a pressure switch. This bypassed the fill valves and let pump run until most of the return water was gone.  When that happened, the pressure switch kicked out and the fill valve took over until the tub was full (or you cheated and hit the Water Saver - whichever comes first...LOL)

I wish I had thought to video this, even though there are still leaks in that system.

But so help me, one day....