Rear wiper with a mind of its own

Noticed my rear wiper playing up last night. It came on randomly when I was driving home from the football and wouldn't switch off until I was parked up. It started randomly stopping rather than returning to the neutral position and it only returned to it's home position on turning the ignition off and then on again.

Is there a simple fix for this? I'm due to drive to Newcastle next weekend - about 200 miles each way. I can live without a rear wiper but since it looks like the front and rear wipers are run off a single fuse on the Mk 2 Fabia, removing the fuse isnt an option.

It's needing serviced in a month. I'm going to try to get my local mechanic to do the service during the week and to look at the rear wiper when it's in. The actual motor still works so I don't know if the motor starting to fail or if its one of the switches that controls the rear wiper?

Just wondering if there's a simple fix to disable the rear wiper in case I can't get it in to my local garage? I've never had the boot door trim off - looks like a single screw and some studs so should be easy enough if disconnecting it is an option?