hi all you Audi experts.

My Q7 seems to make up its mind when the rear wiper works or not, it seems to work even when the lever is off. When switched on it might work once of twice and stop mid screen.

I am awaiting delivery of a second hand motor but this seems more like a wiring issue. Any help please?

Hello Justin,

Have a look a the wiring in the flexible section of the harness which links the body to the tailgate. 
Kind regards,

Gareth. 

Thank you

The rear wiper washer runs through the motor. The seal goes and water gets into the motor making it start and stop on the screen. It’s a rubbish design really but a new replacement on eBay is £30. Tell tale sign is the rear washer jet has poor performance or doesn’t hit the screen at all. Water then runs down into the tailgate and leaks onto the catch at the bottom. Common problem. To take it off you need to remove the top plastic trim off where the boot hinges are then the 2 side trims then the main boot trim. It’s held on with t20 torx screws I think. Put some wd40 on the rear wiper arm after taking off the 13mm nut holding it on as the arms splines seize onto the motor and as it goes through the glass you can’t really give it too much force.