Home › Land Rover › 2020 › Defender 110 First Edition › Repair and Diagnosis › General Information › Specifications Index › Diagnostic Trouble Code Index DTC: Transfer Case Control Module (TCCM) -- Defender/L663 › Diagnostic Trouble Code Index - DTC: Transfer Case Control Module (TCCM) (G2400921) › Description And Operation › Transfer Case Control Module (TCCM) › DTC U0080-88: Vehicle Communication Bus F - Bus off › Possible Causes