"N63R DME Fault Code 20A508 Turbocharger Coolant Pump Blocked This Service Information bulletin supersedes SI B11 03 16 dated April 2016. A Check Control message is active for ""Drive Faulty"". The following fault code is stored in the DME: 20A508 - Engine cooler system: Shut down turbocharger coolant pump due to blockage Auxiliary coolant pump for the turbocharger becomes blocked as a result of its failure."