Avant rear wiper motor electrical fault

Posted: Sun Nov 09, 2014 8:00 pm

Hi all,
My rear wiper has packed up (again) Rolling Eyes

but this time it is not the usual mechanical issue of rusted gears due to a water leak. If I earth the switched live with the wiper stalk engaged the wiper will operate, proving that the gears are fine.
Is the fault likely to be in the wiper motor assembly such as a dodgy circuit board or somewhere in the loom (I hope not the latter!).
Meantime my rear screen de-mister has started to cause interference with the radio when they are both on (CD's are fine) so could this be a related issue?
Hate electrical gremlins.
Grateful for any advice.
Cheers