Hi again,
My drivers side window screen wiper has stopped working,
I can move it up and down the window by hand but nothing when I try it from the car.
Could it be the motor or the spline?
If its only the driver's side and presumably the passenger side is operating it must be something mechanical. Looks like you should check the simple stuff first, as you say splines on the shaft and wiper arm then work back from there .
Hope that's helpful ?