Where is my wiper interval module

[grinlap]

97 Camry. The wiper interval function has completely stopped and when the switch is in that position the wiper operates at the same slow speed as when in the slow position. The fast position works ok. But, when I turn the wipers off (at any speed) they stop immediately where ever they are. They don't go back to the normal stopped position.
My Haynes manual suggests that the "interval module" is faulty but they have no picture or verbal description of its location. Can anyone help me out with the location of the interval module?

Thanks in advance.