Home › Jaguar › 2018 › F-Pace Base › Repair and Diagnosis › Quick Lookups › DTC Index › Diagnostic Trouble Code Index DTC: Automatic Temperature Control Module (ATCM) - F-Pace › Diagnostic Trouble Code Index DTC: Automatic Temperature Control Module (ATCM) › Description And Operation › Automatic Temperature Control Module (ATCM) › DTC B12B9-49: Auxiliary Heater Control Module - Internal electronic failure › Possible Causes