Home >> Jaguar >> 2017 >> XJR Base >> Repair and Diagnosis (Single Page) >> General Information >> DTC Index >> Diagnostic Trouble Code (DTC) Index DTC: Rear Differential Control Module (RDCM) -- XJ/X351 >> DIAGNOSTIC TROUBLE CODE (DTC) INDEX DTC: Rear Differential Control Module (RDCM) >> Description And Operation >> Rear Differential Control Module (RDCM) >> P186A-13 Differential Lock-up Actuator Brake Control Circuit / Open - Circuit open >> Possible Causes