Pit

Hi all, Recently changed the rear subframe on my A6 beforehand the car worked fine. Since the work the car won't start/or try to start. On the dash it says park brake failure but the park brake works. Have retraced all the wires and plugs and all are fine. Use the fault reader it's showing multiple faults on the park break that keep returning when cleared. Has anyone experienced this or know what the issue could be??