Recently my 2009 XF Supercharged gave me a "washer fluid low" warning, so I refilled the reservoir. However, it still gives me the warning and also, when I try the washer, the pump runs but nothing comes out.

I'm thinking it must have run dry, and now the pump needs to be primed. (Would have been nice if it'd warned me the fluid was low BEFORE it ran dry.) If I'm right then it seems like a silly thing to visit the dealer for - does anyone know how to prime the washer pump? I could figure it out but I'm not that interested in pulling random coverings off on an exploratory mission. There's no mention in the manual.

I'm hoping that once the pump is primed the warning will stop, also.

 

I've never experienced the need to prime a windshield washer pump and think it's unlikely that's your problem. Is there a puddle of washer fluid on your garage floor? If not, and if you activate the pump for a minute or more and nothing comes out, there may be a leak somewhere in the output line. If you activate the pump for a long time and eventually something comes out, but you have to do that each time, then there may be a defective check ball/valve (that keeps the fluid from all draining back into the reservoir). It seems unlikely that the low fluid warning is related to a need to prime the pump, as most systems don't measure the fluid level that way.

 

After playing with it a bit, seems like you're right. Wishful thinking on my part. Scheduled service, so I'll find out soon enough.