855 Wagon Rear Washer Problem

My 1997 855 wagon's rear washer no longer works. I can hear the pump
when I hit the button on the stalk, but nothing comes out. It does
uses the same resevoir as the front washer doesn't it? The manual
didn't state otherwise. Can anyone give me any cles as what is wrong
and how to fix it. Thanks.

 

In the rear of the car there is a filter this may be clogged or the check
valve in the tailgate may be clogged

 

In an earlier contribution to this discussion,

I assume that there *is* plenty of liquid in the washer bottle? For saftely
reasons, the takeoff for the rear washer is *above* that for the front
screen - so that when the level gets low, the rear one stops first.

 

How do I get to this filter? the housing on the nozzle looks and feels
pretty secure. Is it inside of the nozzle? Do Ihave to back trace to
some point? Thanks

 

The filter is usually on the right side either behind the trim panel on the
D post or just under the cargo area trim panel