Print Head Alignment test produces only a blank page.

Yes head probably clogged. You can try cleaning head multiple times, I think this is a pigment ink machine, so get only these carts for it

I have had some success placing the removed Canon print head (less cartridges) on a paper towel soaked with Windex. When you push down on the paper towel you can see the ink colors come back up onto the silver screens where each tank attaches to the bottom of the print head. Those screens that don't show ink backing up are probably blocked.
I've had to soak some heads overnight, and some nozzles never recover. I've been told that trying to print with an empty cart in place can overheat/melt the individual nozzles and ruin the print head.