Indesit wd12x and 10 flashes

hi there peeps, i have come across an indesit wd12x and when a program is selected nothing happens apart from door locking and then a short pause of bout 10 to 15 seconds and then the dial starts spinning and 10 flashes of light. No water enters the machine and i can hear the dryer fan motor slowing down when i switch it off at the mains – this is the bit i find confusing cos F10 is a pressure switch fault but confused as to why the dryer fan motor somes on. any ideas ??

thanks in advance graham