[morsing]

Originally Posted by Clifford Pope

There's a valve in the pipe from the bottle to the wipers.
I think it must be designed to require a minimum pressure to open - the gravity of the reservoir not enough, but overcome by the pressure of the pump.

They stick open, because of dirt, or in the case of the similar near the tailgate, shut. I've never been able to make a failed one work.

Oh :-(

I will see if I can find some sort of replacement...