Do these generally completely fail or just stop intermittantely ?

Mine seems to work once stalk/Bootlid/car reset, duration of working varies but eventually stops mid cycle, like a judder. Completely stripped it but nowt astray, so ordered a new one..... but the old one is still going intermittantely.

Not had a problem yet GAFF, but the blade judders on mine :(

Mine did this and it was replaced with no argument by the dealer under warranty. They suggested it was a known problem.