Why are the front and back windscreen washers not working properly on my 2011 Toyota Yaris?

Our 2011 Toyota Yaris Mk2 has problems with both front and rear windscreen washers. The rear one is now barely a trickle, and the front ones seem low on power. I can hear the pump working, so I'm guessing that there's a blockage in a pipe or that the pump is not working properly. Is there anything I can do to diagnose (or even fix) the problem, or am I looking at an expensive garage visit?
Most likely to be due to a kinked washer pipe. Might be trapped in the bonnet hinge.
Answered by Honest John on

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