My mate has a 54 plate A3 3.2dsg with a non functioning haldex. Originally vcds showed a clutch pump fault, however we changed that ( as well as the oil) but the fault remained. We then changed the pressure sensor inside the controller but still had the same error. We've now changed the controller and the error has changed to a pressure lower limit exceeded error but still no functioning haldex and vcds measuring blocks show there is no pressure inside the haldex either now or before we started changing things. Not sure where to go with this now after he's spent £500 on parts without success. Cars only done 35k miles, any idea's?