Audi A2 Electric windows not working
 

Hi can anyone help,have an Audi A2 have had an on going problem with the remote central locking and now the front electric windows on both sides wont work. Garage has tested and cant find the problem although they think it could be something to do with a part behind the door panel- Part is:
BRM-H-8 Z2959802A SIEMENS VDO 105081-105

Any advice welcomed.

Thanks