Hi -I have just bought a Audi A4 Avant Sport TDI(2003 reg) and would welcome advise concerning problem with rear wiper arm which has stopped working.Water pump OK .Front wipers and jets also OK.Does rear wiper motor have seperate fuse or do they both work off same fuse .Do I need special tool to get tailgate trim off to get access to motor? also need to replace cracked speaker grill on rear door -is the grill all part of the door card or is it seperate ? any advise greatly appreciated