Thanks for the replies!

The other possibility that has been suggested by two different dealers is that the 'multi-function' wiper/washer intermittent wiper switch/control stalk might need to be replaced. This is a $133.00 gamble however.

I unplugged the washer reservoir motor today at the dealers' lot, unintentionally dislodging the motor and draining the reservoir in the process. Fortunately the reservoir was already mostly empty.

So has anyone had this 'multi-function' device fail with similar symptoms?