We need some confirmation and details from the OP before reaching any conclusions really. IF PA has really failed then it's a great concern to many of us. however, if (as it sounds) the damage is on the rear of the car then driver error has failed in this case.
"Sleeper 335D xDrive M Sport" Glacier Silver / Black
ZMS | ZNP | ZVI | 2VF | 2VL | 3AG | 494 | 6NS | 8TH