Home › Jaguar › 2014 › XF Base › Repair and Diagnosis › Quick Lookups › DTC Index › Diagnostic Trouble Code (DTC) Index DTC: Gateway Module (GWM) -- XF/X250 › Diagnostic Trouble Code (DTC) Index DTC: Gateway Module (GWM) › Description And Operation › DTC P0A1A-87: Generator Control Module - Missing message › Possible Causes