Home › Land Rover › 2014 › Range Rover Base › Repair and Diagnosis › Quick Lookups › DTC Index › Diagnostic Trouble Code Index DTC: Rear Differential Control Module (RDCM) -- Range Rover/L405 › Diagnostic Trouble Code Index DTC: Rear Differential Control Module (RDCM) › Description And Operation › DTC P1628-62: Module Ignition Supply Input - Signal compare failure › Possible Causes