U DTC codes are often related to wiring issues or the inability to communicate with a sensor or module. 428 is steering angle sensor and 415 is ABS control module. Issues with either the ABS sensors or steering angle sensor could cause the Haldex to remain locked when it should be open which would explain the banging. Terrain response can't function without feedback from the ABS system, so until you sort out the ABS issue you won't get terrain response back.

What was done wrong during the Haldex service? Did the garage let the car battery go flat and then jump start it? Its not unknown for jump starting to damage the cars ECU'S.

A LRF2 specialist told me that the Haldex oil has an extremely bad smell and i was told that when servicing the Haldex,the machanic did not extract the specific 70 ml after filling.Before the Haldex service,the car was running perfectly fine.