98 Sienna rear windows stuck open

The rear window operation has been intermitant for some time, and today stopped all together. It isn't likely that both motors failed at the same time so it must be the power relay that powers them. There are four relays behind the grill of the rear fan in the back of the van. One of these must be the window relay(s). The manual doesn't say what they are. Does anyone know which is the window relay?

I have since determined that the four relays behind the rear fan grill do not go to the rear window motors. I still don't know where the fan relays are. Does anyone know or had this issue before??

Check for the 'PWR-VENT' fuse open. The fuse panel with this one should be low, left of the steering wheel, behind the tiny drawer (where we keep the valet key - or did until the ignition lock seized-up and got replaced).