Home › Jaguar › 2012 › XJ Base › Repair and Diagnosis › Restraints › Restraints Control Systems › Diagnostic Trouble Code Index DTC: Restraints Control Module (RCM) -- XJ/X351 › Diagnostic Trouble Code (DTC) Index DTC: Restraints Control Module (RCM) › Description And Operation › Restraints Control Module (RCM) › DTC B0090-56: Left Frontal Restraints Sensor - Missing message › Possible Causes