Home › Jaguar › 2018 › F-Pace Base › Repair and Diagnosis › Quick Lookups › DTC Index › Diagnostic Trouble Code Index DTC: Telematics Control Module (TCU) - F-Pace › Diagnostic Trouble Code Index DTC: Telematics Control Module (TCU) › Description And Operation › Telematics Control Module (TCU) › DTC U2109-09: Back-up Battery - Component failures › Possible Causes