Home › Land Rover › 2021 › Defender 90 › 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 U3006-85: Control Module Input Power "A" - Signal above allowable range › Possible Causes