The rear window squirter on my wagon isn't working.

The reservoir under the hood isn't leaking anywhere, and looking under the hood liner, it appears someone has used some 'helps' type products to repair the hoses etc in the past. Thinking it might have gotten unplugged at some point.

I see the hose runs through the passenger side of the tailgate, inside the body. Where does this run? Are there common 'failure' points of this system?

Thanks!

 

I know the line runs through the passenger side well under the floor in the back. If you pull up the well cover and kick plate trim, there is a small inline filter that might be clogged. Mine doesn't spray, either. I pulled the trim to adjust the latch (unrelated), but I didn't have time to investigate the filter...

 

I would unplug it at the filter and see if it sprays.

 

on mine, the pump itself went bad. hit the button and have someone listen in the engine bay for it, it works if the car is on "on" does not have to be running.

You need to bleed the system beforehand, what I did was took a 2L bottle of pepsi, filled it with water drilled a small hole in the cap and attached the fluid line, then I squeezed the pepsi bottle intill water started coming out of the rear sprayer, this is also a good way to test for leaks.
Once that's done connect the line to the pump and run it intill you get pressure out the back.

 

There are two washer pumps. Except for taking fluid out of the same reservoir bottle they have different or separate everything.

Under the floor of the wagon the washer hose will run down the passenger side and near the wheel hump or slightly after there is a filter in the line. Up by the sprayer under the trim there is a check valve that is supposed to keep the fluid in the line primed and ready to spray.

Rear Wiper Washer Fluid Pump

Rear Wiper Washer Fluid Check Valve 2 Port

Washer Fluid Filter

The picture is the wagon's rear washer pump and it's behind the bumper on the passenger side frame rail.

 

What Kfrog said. If you hear the pump running when activated by the switch, then 5 will get you 10 that the check valve is clogged; replace the filter too while at it.