Working for a WX radar on company, the largest A320 operator in the world I'm led to believe, I have NEVER encountered or heard of a WX-radar being unserviceable.
Sometimes these topics seem more of a showcase for ones superior airmanship than anything else. In the Air India thread quite a few people could not believe that some companies do not have an After Takeoff Checklist. And yet here these same people can't believe that our SOP demands the radar on all the time. Guys....take a break.